Refactored LookupItemSet to fully exploit National Information Standards Organization Circulation Interchange Protocol
Corrected LookupItemSet with recordId & itemId -> two different services (itemId working now, recordId no)
Added optional scheme links to sample XMLs
Invented unique itemId parsing -> see those XML samples
Added possibility to enable returning empty response (if no service desired) - probably useful for checking existency - disabled by default
Enabled parsing one specific item from Aleph
Created bunch of sample XMLs for maximal efficiency testing (all available services desired & all schemes defined)
Updated GUI for testing (added buttons for new XMLs & enlarged textareas