Fix documentation problems
Remove unused import
Fix ParseTreePatternMatcher.compile allowing invalid syntax
Merge pull request #458 from sharwell/tweaks

Tweaks
4.1->4.2 in doc
Updated maven release configuration
Updated build to include annotation processor in shaded Tool jar
[maven-release-plugin] prepare release 4.2
[maven-release-plugin] prepare for next development iteration
Merge pull request #460 from sharwell/release/4.2
Add regression test for issue #461 (interpreter starting with LR rule)
Return the correct tree when starting parser interpreter at an LR rule (fixes #461)
Merge pull request #462 from sharwell/fix-461

Fix 461