[skip-changelog] Eliminate empty lines produced by board details -b

[MatteoPologruto]

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What kind of change does this PR introduce?

CLI imperfection fix

What is the current behavior?

Running board details -b produces unnecessary empty lines between each Required tool entry.

Required tool:             arduino:arm-none-eabi-gcc                                         7-2017q4

Required tool:             arduino:bossac                                                    1.7.0-arduino3

Required tool:             arduino:openocd                                                   0.10.0-arduino7

Required tool:             arduino:CMSIS                                                     4.5.0

Required tool:             arduino:CMSIS-Atmel                                               1.2.0

Required tool:             arduino:arduinoOTA                                                1.2.1

What is the new behavior?

The empty line has been removed and the spacing between the columns reduced. Also, the Programmer's ID is now written in all caps.

Does this PR introduce a breaking change, and is titled accordingly?

No

Other information

To test the changes, I did not add any new test. However, it was necessary to modify older ones.