app-rdm: overwrite /search endpoint to view dublin-core/search instead

[utnapischtim]

The global search makes it possible to search over all data model (rdm, marc21, lom) and maybe others (communities) too. app-rdm creates per default the /search as the rdm-records search. Which is normally perfect, but for that special case not good. The global search should be on /search and the special searches on special enpoints

/search -> global search (which is dublin-core)
/rdm/search -> rdm-records
/marc21/search-> marc21
/lom/search-> lom

Solution:

overwrite SEARCH_UI_SEARCH_TEMPLATE and create a new endpoint for rdm/search which uses the original value for SEARCH_UI_SEARCH_TEMPLATE

• https://github.com/inveniosoftware/invenio-search-ui/blob/e08e0d3cb0564b539cc0dc7f49dadd3b11f2c7e7/invenio_search_ui/views.py#L24

an overwriting of /records is maybe not necessary. this has to be tested. because it exists /search could then get the response from /api/dublin-coreand /rdm/search gets the response from /api/records