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
Merge remote-tracking branch 'origin/fix-delete' into feature-hover-dialog
Merge remote-tracking branch 'origin/fix-backspace' into feature-hover-dialog

Conflicts:
	spec/support/editor_helper.rb