Merge branch 'abw_sps_to_dhf' into 'master'

hived/dhf_api_plugin.py

...ttest_api_tests/condenser_api/dhf_via_condenser_test.yaml

hived/pyresttest_api_tests/dhf_api/dhf_api_test.yaml

hived/pyresttest_api_tests/dhf_api/find_proposals.json.pat

hived/pyresttest_api_tests/dhf_api/list_proposals.json.pat

...yresttest_api_tests/dhf_api/list_voter_proposals.json.pat

hived/pyresttest_api_tests/dhf_api/request_template.json

hived/pyresttest_api_tests/run_api_tests.sh

hived/reference/condenser_api/README.md