0.5.0

changelog
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- Ignore remote assets in useref.assets(). Fixes #37.
- Strip the BOM in useref.assets(). Fixes #34.
- Expose types as options: only concatenate selective types.
- Fix searchPath for arrays of length 1. Fixes #23.
- Better error handling for missing assets.
- Ignore build blocks with no assets. Fixes #13.