Add a failing test for #7
Put cursor on empty line after return in braces

When return is pressed with the cursor inside a matching pair, add an
empty line between the braces, move the cursor there and autoindent.
Implements the behavior discussed in #7, but breaks some other specs.
Merge pull request #12 from ilkka/curly-brace-autoindent

Leave cursor on blank autoindented line when return pressed within matched pair