Make sure Q library doesn't suppress any exceptions (use done/nodeify after catches).

[ksmyth]

corediff.spec.merge.js throws uncaught exceptions

e.g. https://github.com/webgme/webgme/blob/master/test/common/core/corediff.spec.merge.js#L884 results in:

node ./node_modules/mocha/bin/mocha -R dot --recursive --timeout 10000 test/common/core/corediff.spec.merge.js

unhandled error from callback { [AssertionError: expected '#fa3404d329b0be53648786400db65f301f09b501' to equal '#750269ed92ac349ed65d87ed4a91fe40381ea1a1']
  message: 'expected \'#fa3404d329b0be53648786400db65f301f09b501\' to equal \'#750269ed92ac349ed65d87ed4a91fe40381ea1a1\'',
  showDiff: true,
  actual: '#fa3404d329b0be53648786400db65f301f09b501',
  expected: '#750269ed92ac349ed65d87ed4a91fe40381ea1a1' }

...

1) corediff-merge merge registry changing to the same value:
 Error: timeout of 10000ms exceeded. Ensure the done() callback is being called in this test.

I suggest using q to automatically catch these exceptions like e.g. https://github.com/webgme/webgme/blob/e55cf3a3cb20bb3553156dde6e7730f78d04344e/test/bin/usermanager.spec.js