Supporting boss apps (such as cb_admin) can be included as rebar dependencies.

I'm afraid my OCD also fixed indentation inadvertently.

With this commit, new projects can add to their deps directory a CB app, such as cb_admin.

It will be properly compiled (the Boss way™).

For use as a dependency to a main app :

- in rebar :
```erlang
{deps, [
  {boss, ".*", {git, "git://github.com/evanmiller/ChicagoBoss.git", "HEAD"}},
  {cb_admin, ".*", {git, "git://github.com/evanmiller/cb_admin.git", "HEAD"}}
]}.
```

- in boss.config:
```erlang
{cb_admin, [
    {path, "./deps/cb_admin"},
    {allow_ip_blocks, ["127.0.0.1"]},
    {base_url, "/admin"}
]}
```

If you want to use it with an existing project, get the skel/priv/rebar/boss_plugin.erl from ChicagoBoss, et overwrite <your app>/priv/rebar/boss_plugin.erl