OSX shortcut fix.

closes #2573
- separate different shortcuts by OS detection in markdownEditor.js
Merge pull request #2574 from LazyChild/issue-2573

OSX shortcut fix.
Fix issues with bower assets in tests

- Ensure that there are no spaces in path so `bower install` succeeds
- Ensure that shell:bower is executed before tests are run

Fixes #1702
Merge pull request #2578 from schneidmaster/fix-1702

Ensure libraries are present when running phantom.js test