Test Css asset encoding getter and setter
Update mocha to 2.0.1.
Updated unexpected to 5.0.0beta23, cleaned up test code a bit.
Added missing semicolon.
Test Asset.load errors
Test Asset extension getter and setter
Test Asset rawSrc getter error conditions
Test Asset rawSrc setter
Adapt Asset test som something unexpected ;)
Added failing test for Css asset parseTree setter
Fix Css parseTree setter test