Made live mode more intuitive to use

[sslater11]

I have setup my vim to use 'ga' as live mode, and hated typing ctrl-p to exit it. So I've made some changes and also made it feel a bit more fluid when changing our minds :D.

We can press any of these keys several times to see our alignments change in real time I changed the Enter key to accept the changes, instead of the old Ctrl-P, which felt clunky and odd. We now cycle through different alignments using the 'a' key. We can enter regex mode by typing / at an point. We can align by columns 1-9 by pressing the keys 1-9 at any time. We can align by ALL columns by pressing '*' at any time. We can align just the last column by pressing '-' at any time.

Edit: This is my first time reading and modifying vimscript, and I believe it is error free, but would love a professional's opinion.