Updated documentation
Formatted documentation
Added links to documentation
Updated some wording in the documentation
Added links to documentation
Updated documentation for CommonToken and CommonTokenStream
Merge pull request #438 from sharwell/doc-updates

Documentation updates
No need to run dot when compiling antlr4-annotations
Remove unused field SemanticContext.parent
Mark field PredictionContextCache.cache final
Added missing NotNull and Nullable annotations, and fix a case where it wasn't followed
Merge pull request #439 from sharwell/cleanup

Cleanup
Improve CommonToken cloning performance, and update documentation
ANTLR 4 targets Java 6 at minimum
Update javac options during testing to address overly verbose warnings
Merge pull request #441 from sharwell/java6-minimum

ANTLR 4 targets Java 6 at minimum
Merge pull request #442 from sharwell/test-build-warnings

Update javac options during testing to address overly verbose warnings
Merge pull request #440 from sharwell/clone-token-text

Improve CommonToken cloning performance, and update documentation
Use the fetchedEOF field to often avoid an expensive LA(1) operation in BufferedTokenStream.consume
Merge pull request #443 from sharwell/consume-opt

Use the fetchedEOF field to often avoid an expensive LA(1) operation in consume