Remove deprecated function from KeyCapture
Don't register history keys more than once

Fixes #557
Return a $destroy fn from kC.initCaptures
Refactor destroy fn in keyCapture
Refactor destroy fn again
Destroy tree keybindings when scope is destroyed
Destroy contextMenu keybindings on scope destroy
Start keyCapture documentation
More documentation headers in kC
Merge pull request #561 from latin-language-toolkit/kc_fix

Add de-registering functionality to keyCapture