Fix make_test_data tools script

Method get_connection has been renamed to
get_connection_from_config.

Resource is object not dictionary, so attributes needs to be
accessed that way.

Change-Id: I19e09f3e9077d3346b4361fa6975a3e696e2e765
Related-Bug: #1349791
Extracting make_resource_metadata method

Dividing this method into multiple helps to reuse it in
some tools scripts for generating data.

Change-Id: I45230cd43d82e946fab394c4b6a1fe6b64cd8937
Related-Bug: #1349791
Add the arithmetic transformer endpoint to setup.cfg

The arithmetic transformer patch at
I1b637e5b1d1bb15ed3c3d7ec758d2a684eaccf21 did not
add the new transformer into the setup.cfg's endpoints, so
this patch does.

Change-Id: I465dc34067915297e19bbb1718c8911e579a3112
Merge "Fix make_test_data tools script"
Merge "Extracting make_resource_metadata method"
Merge "Add the arithmetic transformer endpoint to setup.cfg"