Remove files that only make sense on Mac
Remove GPG, iPython files
Vim: remove .gvrimrc.before (only pertained to MacVim)
Remove .gnupg as homesick subdir
Bash: remove Mac-specific code in helpers.sh
Bash: remove Mac-specific commands & aliases
Remove mac-specific git/hg config
Bash: remove Mac-specific stuff from .bash_profile
Bash: add .bash_profile stuff from Ubuntu default

We took the stuff that made sense from Ubuntu's default .bashrc, and
added that to out .bash_profile.
Bash: only add ~/bin to PATH if it exists
Bash: add better .bashrc/.profile support

We want to maintain the bulk of our code in .bash_profile, to make
merging with the Mac branch easier
Bash: change color of $PS1 + add hostname

The default text color of $PS1 is now white-on-light-blue. $PS1 also
now includes the hostname as part of it.
Bash: remove double-alias of `ls`

In the block of code from Ubuntu's default ~/.bashrc that we copied
into ~/.shell_aliases, there was an alias for ls that simply turned on
color. This was clobbering our own alias that turned on color and
enabled long listings and hidden files. The Ubuntu alias has been
deleted.
Bash: add (empty) ~/.bash_logout

This file is sourced by Bash before every logout action. Ubuntu's
default is to clear the screen, but I don't necessarily want to do
that, so I've just commented out the whole file. However, I added it to
the repo for reference, and as a reminder if we want to add future
functionality.
Add ~/.toprc to repo

This file holds our defaults for the `top` command (generated by
running top, setting its preferences to how you like, and writing
out these preferences by pressing 'W').

Presently, it shows mostly CPU usage, CPU Time, Mem %, process name,
username, and a bit more info, sorted by CPU usage.
Bash: fix rbenv support in ~/.bash_profile
Bash: add support for `keychain` utility

This utility manages running and queuerying the ssh-agent password
manager. We've aliased `ssh` and `git` so that running either commands
kicks off the keychain utility.
Merge commit '85779ce6f7509ef5bfda0e310316a1972262ffff' into Linux

Conflicts:
	.homesick_subdir
Merge commit '90b672a1399fc64dca2408ee2db98b11dd8b447d' into Linux
Vim: force 256 color mode for colorscheme

It's possible that color schemes running on linux/ssh may have been
running in low-color (16 color) mode. We've added a command to
hopefully force 256 color mode.