Fix hinting so it always works in an HTML file.

We were not creating a Session if the language of the selection was not javascript.  So when opening an html file, if the cursor wasn't in a javascript section, we would get no hints.
Only init a Session for html & js files
Merge branch 'master' into html-hint-bug

Conflicts:
	src/extensions/default/JavaScriptCodeHints/ScopeManager.js
Don't need to call initializeSession from unittests anymore
Merge pull request #3810 from eztierney/html-hint-bug

Fix hinting so it always works in an HTML file.