Highlight attributes as keyword
Highlight self and super as keyword
Use greedy regex in interpolation highlighting to prevent issues with
expression nested in function calls
Add indent rules for function declaration with attributes
Fix indentation issues with type annotations
Indent multiline hash and array syntax same way as Xcode does
Make commas non sticky, fixes indentation issues with optionals and
implicit unwrapping
Use different lexer rule for case statement in enum to fix issues with
statements indentation inside enum declaration expression
Restructure test for multi-line hash in method call to test against case
compatible with emacs <24.4

Unfortunately, multi-line hash/array syntax with arguments starting on a
new line looks a bit weird in emacs <24.4. In emacs 24.4 smie parser
handles this case a bit differently, it gives a bit more options to
customize rules. I think similar issue presents in other modes too, for
example in ruby-mode.
Merge pull request #29 from ap4y/master

Set of improvements and fixes #1