Edit license slnames to match CPAN::Meta::Spec

CPAN::Meta::Spec is very restrictive about license names, including being case sensitive. A lot of the names in here will result in an "Unknown" license type in the META file. This PR brings these names in-line with the CPAN::Meta::Spec list in case sensitivity and version numbering.

Additionally, Mozilla 2.0 and CC0 are not recognized by the meta licensing yet. As such, they have been entered as open_source and unrestricted, respectively.