Now Lints Upon Save

Whenever the user saves, the plugin will now automatically run the main `jshint` command.
Merge branch 'master' into on-save
Merge branch 'master' into on-save
Clicking on a line with a JSHint error on it, now shows up as a status bar message.
Rename to Jshint
Remove is_javascript checks
Make display_to_status_bar more generic
Make display_to_status_bar work for multiple jshint messages in the same line
Rename a few vars
Run jshint when buffer was modified
Simplify display_to_status_bar even more
Revert msg string to the previous 80 char wrapping
Update node line
Make sure we're only linting javascript files
Add a nicer way of invalidating timers and errors in JshintListener
Merge
Add settings for automatically linting on edit and save
Add a way of modifying settings
Better way of checking if a file is, in fact, JavaScript
Remove timer after invalidation