Improve Markdown integration

* Default Vim configuration detects .md files as modula
* Replaces default config so that .md is detected as markdown

Resolves #71.
Add git-churn script

After you commit a bug fix to a feature branch, find out if the code
you changed to fix the bug is in files that change often:

    git-churn

If the buggy code changes often, find smells and refactor them. Separate
the parts that change often from the parts that don't.

Conversely, avoid refactoring areas with low churn. Refactoring changes
code, and with each change, you risk introducing new bugs.

Example:

     [feature-branch][~/dev/rails-app] churn
     2 app/controllers/accepts_controller.rb
     2 config/database.yml
     4 app/helpers/application_helper.rb
     4 config/application.rb
     9 spec/models/user_spec.rb
     9 spec/spec_helper.rb
    12 spec/requests/dashboard_spec.rb
    13 spec/models/feedback_spec.rb
    19 app/models/feedback.rb
    21 app/models/user.rb
Install Vundle

* Set up Vundle in vimrc.
* Delete old copies of vim scripts.
* Bundles are automatically set up as referenced submodules.
* Ignore .netrwhist files given presence of submodules.
* Set up vundle in install script.
Run specs directly from vim

* Run current spec file.
* Run spec nearest cursor.
* Run last spec that was run.
* Convert s alias to s script, use Zeus if present.
Pass all parameters to the executable
Easier editing for Markdown files

* Automatically enable spellchecking
* Automatically wrap at 80 characters
Update copyright year to 2013
Attach to tmux session w/ current directory name

I've been experimenting with a workflow where I only run long-running
processes in tmux. Examples:

    zeus start
    foreman start
    rake

tmux (or screen) are good at that: maintaining a long-running process
across shell sessions.

Instead of opening another tmux pane for vim and another for git
commands, Rails generators, test runs, etc., I do all of that outside of
tmux in my normal shell window. Those are all targeted, quick, actions.
They are what I am doing *right now*. It's my workspace.

While experimenting with this process, I noticed, I do jump into tmux
more often. Therefore, I wanted a shorter command for attaching to the
tmux session with the same name as the current directory.
Add Heroku scripts

staging:

    staging console
    staging migrate
    staging process
    staging open
    watch staging ps
    staging tail

production:

    production backup
    production console
    production migrate
    production open
    watch production ps
    production tail

load-backup-into:

    load-backup-into staging
    load-backup-into development

Notes on the last command:

* Copy latest production database backup into development database using
  preferred pgbackups + pg_restore method recommended by Heroku.
* Do not assume local development database name.
* Get local database name from config/database.yml.
* This did not previously exist in dotfiles.

Supporting change for these commands:

* Add ~/.bin to the PATH.

https://github.com/thoughtbot/dotfiles/pull/76
Bundle Github color scheme

Fixes https://github.com/thoughtbot/dotfiles/issues/79
Replace s shell script with rspec shell function and alias

* Use a regular alias to make `s` short for `rspec`
* Use an `rspec` shell function to route to zeus when appropriate
* Removes confusion from `s` working differently than `rspec`
* Removes need to use a special alias to get zeus working
Merge branch 'dc-github-color' into upstream
Add aliases for most common git commands
Use Zeus via aliases, rake

* Create `rake` function and `rk` alias.
* Add `z` alias for `zeus`.
* Alias `migrate` to `m` given how common a task it is.
Pass arguments from rspec shell function when not using zeus

* Non-zeus path didn't pass arguments, so it just ran `rspec`
Bundle Ctrl+P

Full path fuzzy file, buffer, mru, tag, ... finder for Vim.
https://github.com/kien/ctrlp.vim
Updated zlogin and gitconfig files for my custom stuff.
Added snipMate to my dotfiles.
Added new color scheme and ctrlp
Added support for folds.