Update dup calc test to expect qname matching.
Update xbrl.get_calcs to compare qnames.
Update calc tests to expect a namespace prefix.
Reformat line length to stay within PEP8.
Correct test class names.
Update xbrl.get_linkbase to use the DTS.
Update tests to expect file prefix.
Update parse_xmlns to handle a default namespace.
Allow graceful fail for opening calc linkbase.
Allow unit utility to handle prefix-less measures.