Replace snipmate with UltiSnips
Set up basic structure for Swift bundle
Add basic Syntastic support to Swift
Port :SwiftRun to the Rust-style architecture

This compiles and runs the file instead of using immediate mode.
Fix the Syntastic swift IsAvailable() check

It was executing `xcrun swift`, which takes a while to load up LLDB.
Instead it should be using `xcrun -find swift`.
Start defining Swift syntax
More syntax work
Match comment blocks better

Fix the /* */* comment issue.

Also mark operators as transparent.
More syntax support
Support attributes
Finish up Swift syntax highlighting

At this point, it looks largely correct and I think everything is
covered. There's some interesting oddities like the block associated
with a for-loop is actually treated as a closure, but I don't think that
really matters.

Indentation still needs to be set up properly.
Switch from cindent to smartindent

cindent doesn't work well because of the lack of semicolons. Smartindent
should provide acceptable behavior for now.
Add Boolean literals
Highlight unbalanced string literals as strings