BREAKING CHANGE: Rework of the Grunt Closure Linter plugin.

- Cleaned up Grunt options and moved the converter to
the folder /tasks/lib/converter for a feature
based folder structure.
- The ctools.js has been replaced by the common.js
and commandrunner.js
- Updated dependencies (package.json)
- Some more housekeeping
fix(Linter): Fixed linter error.

JSHint (since version 2.0.0) will throw the "ES5 option is now set per
default" error when it encounters the es5 JSHint option with a value of
true.
chore(Gruntfile): Disabled test task

Disabled test task as we've no test sets so far.
Merge pull request #12 from subesokun/rework

Rework of the Grunt Closure Linter plugin