Readme changes

I missed these two when I was going through the first time. "ot" to "to"
and "github" to "Github".
Grammar change
Fixes Issue #26
Fixes typo in lesson 1.3 alert steps modal

I noticed there's a typo in the 1.3 alert modal.  If you follow the
directions to the T, it won't pass because it commits to the wrong
branch.

It needs to say make a new branch called `bugFix`,
then `git checkout bugFix`, then commit.

Screenshot with commands in working order:
http://cl.ly/image/3V0n192R1p21

Tests Pass:
13 tests, 13 assertions, 0 failures
I couldn't get it to build to test the text displaying in browser, so
that still needs to be tested.
Thanks Adam Brodzinski for the pull
Fixes Issue #19 thanks a ton epheph
readme
Fixes Issue #30
readme
Added common git aliases.

git ci => git commit,
git co => git checkout,
git st => git status,
git br => git branch
Tweaked window buttons and themes
Update src/levels/intro/4.js

Fixed minor typo in instructions.
Rebuilding css and hashing for deployment, thanks Hamish Macpherson
Rebuilding for Lukes pull
rebuilding for CameronWills
Recursive tree comparison algorithm that is hash agnostic to lay the groundwork for Issue #28
better tree comparsion from Issue #28
Better goal tree and hint and solution. Fixes Issue #37
Fixes Issue #36
readme