Fix delete at end of feature

Now should be able to delete past the end of a feature.
[fix-backspace] Allow user to backspace past the beginning of the line again.
Add regression tests
More trying to fix deleting
Merge remote-tracking branch 'origin/fix-backspace' into fix-delete

Conflicts:
	spec/support/editor_helper.rb
Add some more tests, and fix a bug with deletion
Fix undo/redo
Merge remote-tracking branch 'origin/master' into fix-delete
Remove save_screenshot calls
Merge pull request #61 from GorillaApp/fix-delete

Fix delete at end of feature and backspace near the beginning