archibald 7.x-2.3

New features
- Added field to enter «Size» of resource
- Added field to enter «Format» of resource
- Added field to enter «Copyright description» for preview image
- Added field to enter «Duration»
- Learning Resource Type is now either «Documentary» (mandatory field) or «Pedagogical» (optional field)
- Added context help bubbles in entry form
- Added button to reset search results in the administration area
- Enabled translation for all langstrings in descriptions
- Checks format when adding a URL in the field «Location»
- Implemented display of title for ISBN and DOI identifiers

Changes
- Overall layout improvements
- Enabled immediate deletion of descriptions
- Removed field «Copyright and other restrictions»
- Changed value of the field Meta-Metadata Catalog to «archibald»
- Changed value of the field Metadata Schema to «LOM-CHv1.1»
- Changed handling of related resources according to LOM-CHv1.1
- Values for typical learning time are now kept as vocabulary, the conversion to minutes is not used anymore
- Changed handling of preview images, they are no longer cropped but scaled
- Enabled addition of multiple locations

Bug fixes
- Fixed loss of translated keywords when saving a new revision
- Ensured that all vocabularies are retrived from the ontology service
- Numerous minor bug fixes