bashrc: added color for `ls` and `grep`

Apparently these never existed in my personal bashrc file. They're
included in the default bashrc file that you get when Ubuntu is
installed, and since I mostly use Ubuntu, I never noticed before.

NOTE: some platforms (like BSD) use don't use `--color=auto` for
colored ls output (I've seen both `colorls` and the `-G` flag). For
these platforms, I guess you'll have to manually change that line.
Boo hoo
bashrc: removed `pageant` alias directive

I've moved it over to my `~/bin` directory because I wanted to make it
have more logic and it was too complicated for a simple alias