Gracefully handle 'catch' and 'finally' blocks without a preceding 'try' block.

Fixes #216.

As a note of this fix, when a 'catch' block is followed by a 'finally' block, only the 'catch' keyword gets an error reported on it.
Added tests for missing 'try' parsing
Simplified error recovery by just using 'parseTryStatement'.
Merge branch 'master' into trylessCatchesFinallyParseNicely

Conflicts:
	src/compiler/diagnosticMessages.json
Merge pull request #262 from Microsoft/trylessCatchesFinallyParseNicely

Improved errors for 'catch'/'finally' blocks missing 'try' statements