Made color settings in Xresources more general.

Before this change, the color settings only applied to xterm and not to
other X applications (like xclock.) This makes the background and
foreground applicable to all X applications.
My .zshrc now looks for a local file to source for local settings.

There are some settings that I do not want to have on multiple machines,
but would rather keep to one machine or machine class. (For example, CS
department specific PATHs.) My zshrc will now look for a local file from
which to load such settings.
zsh: Add current git branch to prompt.

Conflicts:

	zsh/zshrc
Changed PS1 to look like the adam PS1.