Generate stuff before building.

Kinda obvious.
Use proper Gem names for checksums.

This ensures that it also works for JRuby and the likes.
Added checksum for 0.1.1 on JRuby.
Ignore casing when testing for html void elements

Fixes #36
Fix test cases

- Remove duplicate tests
- use parse_html helper
Added a lexer test case for uppercase void elements
Change Hash syntax to be consistent with other tests
Merge pull request #39 from ttasanen/fix_uc_void_tags

Ignore casing when testing for html void elements