Merge pull request #13 from Dicebot/d1

Support for -version=D1 output
Don't ignore header files in test_files.
Remove vim .swp file.
Change forward struct delcaration generation.

Was: struct Name { }
Now: struct Name;
Add vim .swp files to gitignore
Prevent duplicate structs.

Output forward declared structs only if no definition was found.
Fixes Issue #5, relevant test files added.