Bugfix getContentResources
Bugfix getContentResources

 - Fix log messages.
 - Return invalidOperation fault when adapter returns an empty resourcs
 array, which idicates that the content has not yet been issued.
 - Capitalize letter 't' in mimetype. Adapter shall return arrays
 which contain key 'mimeType', not 'mimetype'.

kolibre/Kolibre-KADOS