Remove reference to therubyracer from README.md 

therubyracer doesn't currently work to build ember.js, and this patch removes an instruction to use it.
Fix two linkTo unit tests that fail in IE9.  Tests used an <a> tag inside of a <button> tag, which IE9 does not like but works in other browsers.  Example: http://jsbin.com/ozemig/1/edit
Normalize controller lookup, fix #2025
Merge pull request #2145 from craigteegarden/ie9-linkTo-test-fix

Fix two linkTo unit tests that fail in IE9.  Tests used an <a> tag insid...
Merge pull request #2131 from darthdeus/normalize-controller-lookup

Normalize controller lookup, fix #2025
Reuse path variable
Refactor normalization
Merge pull request #2152 from darthdeus/fix-normalization

Refactor normalization
Merge pull request #2151 from caligo-mentis/reuse_variable

Reuse path variable in Ember.HashLocation
Use ENV var to disable version logging of used libraries
Merge pull request #2090 from regularfry/master

Patch to avoid bumping into issue #2069
object proxy defines properties that are passed to create that do not exist in the prototype
expose RSVP on the ember namespace
Merge pull request #2162 from stefanpenner/master

Expose RSVP on the Ember namespace
Merge pull request #2155 from javierav/debug

Use ENV var to disable version logging of used libraries
Update ember-views/lib/system/utils.js to handle innerHTML issues with IE better. Fixes issue #2018