Add a new keymap `ctrl-backspace`
Add a feature for removing matching brackets
Add a new menu item
:white_check_mark: Add tests

Tests for the `remove matching brackets` feature
Merge pull request #51 from baldurh/delete-matching

Add feature to remove matching brackets
Only remove brackets in single cursor mode
Support deleting matching pair of selected pair
Prepare 0.49.0 release
Only use ctrl-backspace on Mac

ctrl-backspace deletes to beginning of word on Linux and Windows so
use ctrl-alt-backspace on those platforms for deleting matching bracket
Prepare 0.50.0 release
Merge branch 'master' into chrome35

Conflicts:
	package.json