`editor.keyboard`
Document binding keyboard shortcuts.
Bind undo/redo keyboard shortcuts.
Some more keyboard shortcuts.
More sane require path for object-history in globalifier file.
Merge branch 'issue_512' into kb-shortcuts

Conflicts:
	src/wymeditor/editor/object-history-globalifier.js
More sane require path for Combokeys.
Run additionnalAssertionsFunc after redo in testWymManipulation
Merge branch 'issue_512' into kb-shortcuts
Add a keyboard event "simulator".
testWymManipulation: add keyboard shortcut testing option
Use testWymManipulation's manipulationKeyCombo in two undo/redo tests.
Keyboard shortcuts for italic and bold use `exec` instead of `_exec`.
Don't load Keysim (used in tests) in IE <= 8.
testWymManipulation doesn't test keyboard shortcuts in IE <= 8
Use a branch of keysim that includes a fix for IE9 through 11.