Updated NominetDomainExtensionBase _ns

Updated the namespace used for NominetExtensionBase from
http://www.nominet.org.uk/epp/xml/domain-nom-ext-1.0 to
http://www.nominet.org.uk/epp/xml/domain-nom-ext-1.2
Trying to fix domain release
Fixed Domain Release

Fixed DomainRelease not producing correct xml and added test.
Domain Release Tests

Added tests for Domain Release
NominetDomainInfoResponse fully populated

Fixed issue with NominetDomainInfoResponse not being fully populated
because of an incorrect namespace.
Merge remote-tracking branch 'upstream/master'
Merge pull request #7 from eyoung1980/master

Fixed missing data in NominetDomainInfoResponse