OAR Properties generator: add support for per-core properties (including GPU)

Gemfile

Gemfile.lock

Rakefile

lib/refrepo/gen/oar-properties.rb

scripts/nvidia-numa-mapper.rb

tests/oar_properties_spec.rb

...s/stub_oar_properties/dump_oar_api_configured_server.json

tests/stub_oar_properties/dump_oar_api_empty_server.json

...stub_oar_properties/load_data_hierarchy_stubbed_data.json