linkbacks: jinja base templates renaming

Signed-off-by: Eirini Psallida <eirini.psallida@cern.ch>
messages: jinja base templates renaming

Signed-off-by: Eirini Psallida <eirini.psallida@cern.ch>
oauth2server: jinja base templates renaming

Signed-off-by: Eirini Psallida <eirini.psallida@cern.ch>
pages: jinja base templates renaming

Signed-off-by: Eirini Psallida <eirini.psallida@cern.ch>
records: jinja base templates renaming

Signed-off-by: Eirini Psallida <eirini.psallida@cern.ch>
cloudconnector: jinja base templates renaming

Signed-off-by: Eirini Psallida <eirini.psallida@cern.ch>
access: file renaming

*Moves files to `admin/` directory

Signed-off-by: Eirini Psallida <eirini.psallida@cern.ch>
search: jinja base templates renaming

Signed-off-by: Eirini Psallida <eirini.psallida@cern.ch>