Add frequently used key combinations

I'm in the process of adding a few key combos:

[ ] ^A - move to beginning of line
[ ] ^E - move to end of line
[ ] ^K - kill all text after the cursor
[x] ^H - delete character before cursor

I'm going to keep pushing to this branch and opening pull-requests (if this one is not still open.) 

@garyberhnardt if you're not interested in these let me know and I won't bother with the pull-requests. Thanks!