Merge pull request microsoft#49 from wravery/master

Couple of fixes

Fix microsoft#44 - Handle schema extensions

Merge pull request microsoft#40 from wravery/master

Fix microsoft#39, plus a lingering short-string-optimization bug

Fix microsoft#39, plus a lingering short-string-optimization bug

Merge pull request microsoft#38 from wravery/master

Fix issue microsoft#37

Merge pull request microsoft#36 from Microsoft/operationtypes

Expose findOperationDefinition to fix microsoft#34

Fix issue microsoft#37

Fix merge conflict in last cherrypicked commit

Merge pull request microsoft#32 from wravery/enum_args

Fix for issue microsoft#30

Update samples and visitEnumValue methods