Better support for partial buffer reads/writes in translog infrastructure

Some IO api can return after writing & reading only a part of the requested data. On these rare occasions, we should call the methods again to read/write the rest of the data. This has cause rare translog corruption while writing huge documents on Windows.

Noteful parts of the commit:
- A new Channels class with utility methods for reading and writing to channels
- Writing or reading to channels is added to the forbidden API list
- Added locking to SimpleFsTranslogFile
- Removed FileChannelInputStream which was not used

Closes #6441 , #6576