DDF-51: Modified links to not navigate away from search page.
Extensible Metacard unregister and list registered types functionality.
DDF-49: MetacardTypeRegistry immutability of registered types set.  Clean up of logging statements.  Test comparing a QualififedMetacardType with a MetacardType.
Merge pull request #3 from codice/ddf-extensible-metacard

DDF-49: Merge the ddf extensible metacard functionality into master.
DDF-38: Added SearchPage help content and updated about to help that directs to help page
DDF-38: Cleaned up dead html
DDF-36: Cleaned up accidental change that shouldn't have happened
DDF-38: Updated Header in SearchHelp.html
Merge pull request #4 from millerw8/master

DDF-36, DDF-38
DDF-38: Fixed help document typo.
DDF-38: Removed intro help section for clarity.