Add documentation when application developers need to close things

[sammefford]

Many io handles require application developers to close the InputStream or other entity received from get(). We need to clearly document when application developers have a responsibility to close connections. Some handles off-hand to look at that might need this documentation: InputStreamHandle, ReaderHandle, InputSourceHandle, SourceHandle, JacksonParserHandle, XMLStreamReaderHandle, XMLEventReaderHandle, FileHandle, OutputStreamHandle,

[nikos]

+1