Added Msrp documentation

Author: ProkopovVitaliy

app/code/Magento/Msrp/README.md

@@ -1,6 +1,6 @@
 # Magento_Msrp module
 
-The Magento_Msrp module is responsible for Manufacturer’s Suggested Retail Price functionality.
+The **Magento_Msrp** module is responsible for Manufacturer’s Suggested Retail Price functionality.
 A current module provides base functional for msrp pricing rendering, configuration and calculation.
 
 ## Installation
@@ -35,6 +35,22 @@ For information about a typical file structure of a module in Magento 2,
 
 ## Extensibility
 
+ Developers can pass custom `msrpPriceCalculators` for `Magento\Msrp\Pricing\MsrpPriceCalculator` using type configuration using  `di.xml`. 
+ 
+ For example:
+ ```
+    <type name="Magento\Msrp\Pricing\MsrpPriceCalculator">
+        <arguments>
+            <argument name="msrpPriceCalculators" xsi:type="array">
+                <item name="configurable" xsi:type="array">
+                    <item name="productType" xsi:type="const">Magento\ConfigurableProduct\Model\Product\Type\Configurable::TYPE_CODE</item>
+                    <item name="priceCalculator" xsi:type="object">Magento\MsrpConfigurableProduct\Pricing\MsrpPriceCalculator</item>
+                </item>
+            </argument>
+       </arguments>
+   </type>
+``` 
+ 
  Extension developers can interact with the Magento_Msrp module. For more information about the Magento extension mechanism, see [Magento plug-ins](https://devdocs.magento.com/guides/v2.4/extension-dev-guide/plugins.html).
 
 [The Magento dependency injection mechanism](https://devdocs.magento.com/guides/v2.4/extension-dev-guide/depend-inj.html) enables you to override the functionality of the Magento_Msrp module.

app/code/Magento/MsrpConfigurableProduct/README.md

@@ -1,3 +1,34 @@
-# MsrpConfigurableProduct
+# Magento_MsrpConfigurableProduct module
 
-**MsrpConfigurableProduct** provides type and resolver information for the Msrp module from the ConfigurableProduct module.
+The **Magento_MsrpConfigurableProduct** module provides type and resolver information for the Magento_Msrp module from the ConfigurableProduct module.
+Provides implementation of msrp price calculation for Configurable Product.
+
+## Installation
+
+For information about a module installation in Magento 2, see [Enable or disable modules](https://devdocs.magento.com/guides/v2.4/install-gde/install/cli/install-cli-subcommands-enable.html)
+
+## Structure
+
+`Pricing\` - directory contains implementation of msrp price calculation 
+for Grouped Product (`Magento\MsrpGroupedProduct\Pricing\MsrpPriceCalculator` class). 
+
+For information about a typical file structure of a module in Magento 2,
+ see [Module file structure](https://devdocs.magento.com/guides/v2.4/extension-dev-guide/build/module-file-structure.html#module-file-structure).
+
+## Extensibility
+
+ Extension developers can interact with the Magento_Msrp module. For more information about the Magento extension mechanism, see [Magento plug-ins](https://devdocs.magento.com/guides/v2.4/extension-dev-guide/plugins.html).
+
+[The Magento dependency injection mechanism](https://devdocs.magento.com/guides/v2.4/extension-dev-guide/depend-inj.html) enables you to override the functionality of the Magento_Msrp module.
+
+### Layouts
+
+For more information about a layout in Magento 2, see the [Layout documentation](http://devdocs.magento.com/guides/v2.3/frontend-dev-guide/layouts/layout-overview.html).
+
+### UI components
+
+For information about a UI component in Magento 2, see [Overview of UI components](http://devdocs.magento.com/guides/v2.3/ui_comp_guide/bk-ui_comps.html).
+
+## Additional information
+
+For information about significant changes in patch releases, see [2.4.x Release information](https://devdocs.magento.com/guides/v2.4/release-notes/bk-release-notes.html).

app/code/Magento/MsrpGroupedProduct/README.md

@@ -1,3 +1,39 @@
-# MsrpGroupedProduct
+# Magento_MsrpGroupedProduct module
 
-**MsrpGroupedProduct** provides type and resolver information for the Msrp module from the GroupedProduct module.
+**Magento_MsrpGroupedProduct** module provides type and resolver information for the Msrp module from the GroupedProduct module.
+Provides implementation of msrp price calculation for Grouped Product.
+
+## Installation
+
+For information about a module installation in Magento 2, see [Enable or disable modules](https://devdocs.magento.com/guides/v2.4/install-gde/install/cli/install-cli-subcommands-enable.html)
+
+## Structure
+
+`Pricing\` - directory contains implementation of msrp price calculation 
+for Configurable Product (`Magento\MsrpConfigurableProduct\Pricing\MsrpPriceCalculator` class). 
+
+For information about a typical file structure of a module in Magento 2,
+ see [Module file structure](https://devdocs.magento.com/guides/v2.4/extension-dev-guide/build/module-file-structure.html#module-file-structure).
+
+## Extensibility
+
+ Extension developers can interact with the Magento_Msrp module. For more information about the Magento extension mechanism, see [Magento plug-ins](https://devdocs.magento.com/guides/v2.4/extension-dev-guide/plugins.html).
+
+[The Magento dependency injection mechanism](https://devdocs.magento.com/guides/v2.4/extension-dev-guide/depend-inj.html) enables you to override the functionality of the Magento_Msrp module.
+
+### Layouts
+
+For more information about a layout in Magento 2, see the [Layout documentation](http://devdocs.magento.com/guides/v2.3/frontend-dev-guide/layouts/layout-overview.html).
+
+### UI components
+
+For information about a UI component in Magento 2, see [Overview of UI components](http://devdocs.magento.com/guides/v2.3/ui_comp_guide/bk-ui_comps.html).
+
+## Additional information
+
+### collection attributes
+
+Module adds attribute `msrp` to select for the `Magento\Catalog\Model\ResourceModel\Product\Link\Product\Collection` 
+in `Magento\MsrpGroupedProduct\Plugin\Model\Product\Type\Grouped` plugin.
+
+For information about significant changes in patch releases, see [2.4.x Release information](https://devdocs.magento.com/guides/v2.4/release-notes/bk-release-notes.html).