bump ember-source
Version bump - 0.13
Revert "Version bump - 0.13"

This reverts commit e79d279383231e933de869da8139d7e6cc798f66.

Going to sneak in some improved error logging
Log the error message, not the error class

This actually provides useful error messages. Previously you'd see
"TypeError" on the console. This is not useful. Now you'll see "fooBar()
is not a method". This lets you track down exceptions
Merge pull request #1004 from ahawkins/better-errors

Log the error message, not the error class
Revert "Revert "Version bump - 0.13""

This reverts commit f76848510208136a1fb74bb4db0926e15624e125.