Feature - Migrate mjanez/ckanext-scheming to use a Vanilla ckan/ckanext-scheming

[mjanez]

• [x] Migrate templates
• [x] Migrate helpers
• [x] Update i18n
• [x] Create a folder called scheming/schemas and store the schemas: ckan_geodcatap.yaml, ckan_group_geodcatap.json and ckan_org_geodcatap.json. Also all new schemas (DCAT-AP-ES, DCAT-AP-UE, etc.)
• [ ] Create a schema named:ckan_dcat.yaml with limited metadata elements based on the core DCAT to use by default with facet_scheming.

[mjanez]

mjanez/ckanext-scheming tasks must be added:

1. https://github.com/mjanez/ckanext-scheming/issues/7
2. https://github.com/mjanez/ckanext-scheming/issues/8
3. https://github.com/mjanez/ckanext-scheming/issues/10

[mjanez]

Fix: https://github.com/mjanez/ckanext-scheming/pull/19#issuecomment-1663969602