Update tests to be more thorough

[kdheepak]

I'm submitting a ...

• feature request

Feature Request

Update tests so that they are more complete

e.g. some tests need params

assert dss.Bus.GetUniqueNodeNumber()
assert dss.Circuit.Capacity()
assert dss.Circuit.SetActiveBusi()
assert dss.CktElement.Close()
assert dss.CktElement.IsOpen()
assert dss.CktElement.Open()
assert dss.CktElement.Variablei()

[PMeira]

Monitors also need more tests. Probably adding one or two monitors via run_command() in https://github.com/NREL/OpenDSSDirect.py/blob/30a2060ef1b6986be3a80a49a5b474951d994109/tests/test_opendssdirect.py#L1965 and validating the results is enough.

[kdheepak]

Note for future reference: See issue #29 and PR #30 to identify many functions that are not currently tested.

[PMeira]

The new modules Parallel and Storages are missing tests now, as well as some recent other new functions in other modules.