List fixed bugs in changelog
Stub parsers for CoffeeScript and Lua

Those are the ones I want to work on next.
Closes #21
Improve logic when to skip running an update
Speed up file-type matching

Use end_with?() instead of a regex, and be more precise when checking for a
shebang line (#!ruby or similar). The old shebang method, in particular, would
sometimes read a substantial chunk of binary files just to check the first two
bytes.
Even faster shebang-line matching

Use include?() instead of a regex