Battleschool

- 46 & 37 fixed installs on OS X El Capitan. Moved battleschool files to `/usr/local`
- 39 via 40 added `--use-default-callbacks` option to use ansible callbacks for things like prompting vars via OldhamMade.
- 38 fixed some error printing bugs via OldhamMade.
- 42 add remaining password options from updated ansible via dochang.
- 45 updated usage on readme via vladdancer.

- 33 extra vars parse error with ansible v1.9.1 via subsetpark

- 25 battleschool now supports ansible v1.9.1 and it is required (thanks to eyadsibai for pointing me to dochang's initial fix https://github.com/dochang/battleschool/commit/e54ded165dd80060741b844cb2f09877b1b4f6d6). The new short option for `--update-sources` is `-X`.

- 28 added script_postfix and script_data params to mac_pkg (for homebrew install)

- require ansible version <= 1.8.4 see 25 for support of ansible 1.9.x

- merged 23 by OldhamMade allow use of battleschool as a library