Fix warning when comment does not contain directive
Merge pull request #1 from lightster/fix-non-directive-warning

Fix notice/warning when comment does not contain directive
getJsWebPaths will no longer give a list of duplicate paths
Ticket: #2
Purpose of Change: Sprocketeer\Parser#getJsWebPaths() returns multiple web paths per file
Description of Change:
 * Added a test to make sure the web paths are not duplicated