Added documentation to key bindings.

Conflicts:
	lib/key-bindings.zsh
forgot to save before committing. doh
Don't clobber standard Esc+. behavior

Esc+. works as "last arg" on both bash and zsh. Seems like a shame to introduce a new standard.

Conflicts:
	lib/key-bindings.zsh
Make sure the terminal is always in application mode when zle is active.
Replace hardcoded key escape sequeneces with dynamic ones from terminfo.
Merge pull request #1355 from F30/key-bindings

Use terminfo key codes instead of hardcoded ones for key bindings