Non-functional documentation updates.

- Added CHANGES.md file that contains changelog from version to version
- Removed redundant javadoc markup
- Corrected typos.
Updated @ExpectedPerformanceProfile

- Renamed CACHE_BOUND to CACHE_HEAVY to the Kind enum
- Removed LOW_LATENCY from the Kind enum
- Added SYNCHRONOUS and ASYNCHRONOUS to the Kind enum
Updated CHANGES.md and README.md for next release.