Added SublimeText Project Generator

- Added generator to create project files for SublimeText
- Adds import folders to the project for navigating etc.
-  Generated project inlcudes build systems to invoke DUB build test or run from inside SublimeText

Usage
dub generate sublimetext
How about some fancier stuff, like build-release and build-debug, or do you have any other idea for selecting build configurations?