RNDT: improvements and fixes.

- Some fixes for rasters (checkPointDescription and cornerPoints) [tobia]
- RNDT: improvements for datoPubblico constraint. Schematron improvements for constraints checks. [etj]
- Fixed metadata constraints presentation and small fixes for nilreason in gmd:pass and hierarchyLevel [tobia]
- RNDT: schematron: added rule for empty codelists; improved ResponsibleParty rules [etj]
- RNDT: add helper for useLimitation [etj]
- RNDT: schematron: fixed for pointOfContact, nilReason checks. [etj]
- RNDT: fix text node in codelist elements. [etj]
- Fixed gmd:pass check/composition and positional accuracy [tobia]
- RNDT: fix namespace declarations in CSW full [etj]
- Small fixes for templates and additional fixes for metadata edit [tobia]
- Some fixes for keywords, thesaurus, topicCategory and others [tobia]
- Fixed the gml namespace version in export and csw present. [tobia]
- Removed the identifier element from the flat exceptions [tobia]
- Fix for gmd:voice [tobia]
- Fixed the gmd:date field in edit mode [tobia]