Added the beginnings of the navigation tests

I still need to refactor the methods but at this point, all tests work
Refactored Navigation Methods
Fixed errors in spacing and refactoring out of scenario
Fixed the need of a global variable
Fixed naming issue and hopefully clicking issue
Fixed weird issue of needed to sometimes first find then click instead of css_click
Modified the abtest module to work with fixed preferences scope.

abtest is still untested.  Use not recommended.
Fixed the preferences scope of xblock.

Added self to authors.
Merge branch 'origin/master' into felix/prefsscopefix2

e is necessary,
Merge branch 'master' of https://github.com/edx/edx-platform into felix/prefsscopefix2