Whitespace
Add test cases highlighting failing integer constant lexing.
Fix failing hexadecimal lexing.
Fix the antiquoters for `long long` and `unsigned long long`.
Merge pull request #20.
Fix pretty-printing of $ty antiquoters to match the lexer.
Merge pull request #21.
Fix parsing of property attribute lists (ObjC)

Fixes #24
Merge pull request #23.
Expose ToIdent.
Merge pull request #25.
Merge pull request #27.
Fix documentation for the $id antiquoter.
Document the ToIdent and ToExp classes.
Add support for more flexible constant antiquotation.

Constants can now be antiquoted using the $const antiquoter. The
antiquoted value must be an instance of 'ToConst'.
Adjust upper bounds for new version of symbol package.
Adjust copyright noticies.
Bump version and adjust tested-with field.