Merge pull request #419 from glowing-bear/glyphicon

Use "off" glyphicon instead of "remove"
Add necessary files for unit tests setup
Add unit test setup files and sample plugin unit test
Add instructions on how to run the tests
Make travis run the tests
Add tests for all plugins
Documentation; make test file executable, jshint tests, add a gitignore
Don't fail failed tests by accessing undefined members

If a plugin didn't recognize something it should have recognized, don't fail in
checking whether it failed.

Also, semicolons.
Use valid test URLs
Add tests for Gist & Tweet plugins
Test images with GET parameters as well (#414)
Setup end to end testing

Add necessary targets in the package.json file
and update test instructions
Add sample E2E test