Measurements improvements

[msweier]

This PR:

1. Adds datatype check for measurements to ensure a list of dictionaries is supplied.
2. Reorders the columns returned by the measurement dataframe. For some reason the API returns units first instead of the PKIDs and data. This code seems a bit long for what it does, so I'm open to ideas. I don't want to clutter up the cwms_types.py too much but I don't know of a better way to get the important stuff up front.
3. Adds a get_measurements_extents function.
4. Adds an measurement example notebook.

[sonarqubecloud]

Quality Gate passed

Issues
5 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud