Add spec for keywords() with non-keyword parameters

When passing non-keyword arguments to keyword( $args ) the expected result is an empty map "( )" – like when no arguments are passed – Throws: "Error: basic_string::basic_string"
Add spec for url() munging
Add and activate specs for unique-id()
Merge pull request #150 from xzyfer/wip/issue_636

Add and activate specs for unique-id()