setup: removal of unnecessary requirements.txt

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>
Invenio-Client v0.1.0

Reviewed-by: Tibor Simko <tibor.simko@cern.ch>
Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
version: post-release version bump

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>