Implement Haikuporter recipe syntax highlighting

[extrowerk]

Like Pe does, it is really helpful to know, what is a real keyword, and wich not.

[waddlesplash]

Seems fixed?

[KapiX]

The issue is I think lack of highlighting for app:, cmd: etc. That would require modifying bash lexer, which I didn't get around doing yet.

[KapiX]

The most important part of this issue is solved (highlighting env vars, built-in vars and shell scriptlets). Highlighting for app:, cmd:, etc., variables and comments inside strings will require more invasive changes to the lexer. Additionally it has weird distinction between $ and ${} vars. However, Pe didn't support that either, so I consider this fixed and the rest goes to the post-1.0 backlog.