Added getOccs support for if/else keywords, and some tests.
Addressed CR feedback, no longer highlighting elseifs with comments between.
Added test case for broken if-elses.
Added missing break statement.
Use isWhitespace in getIfElseOccurrences.
Added getOccs support for return keywords.
Added tests for getOccs on return keywords.
Utilize getContainingFunction in services.
Merge pull request #561 from Microsoft/getOccurrencesIfElseIfElseIfElse

getOccurrencesAtPosition support for if/else keywords
Addressed CR feedback.
Merge branch 'getOccurrences' of https://github.com/Microsoft/TypeScript into getOccurrences
Addressed more CR feedback.
Merge pull request #593 from Microsoft/getOccurrencesReturn

Get occurrences for return keywords.
getRefs/getOccs support for 'this' keyword.
Added fourslash tests for 'this' keyword findOccs/findRefs.
Made a getThisContainer function.
Addressed CR feedback.
Basic implementation without tests for findAllRefs/getOccs for 'super' keywords.
Added tests for getOccurrences on super.
Merge pull request #600 from Microsoft/getOccurrencesThis

Get occurrences for 'this' keywords