#2363 data source X, Y, Z arguments inconsistent

[Jeremy Faden]

The X,Y,Z arguments to data sources slid sloppily into existence, and are not consistent between sources. It's been very useful to have this feature, and this should be developed completely. This is to catalog the differences and standardize the behavior.

1. X,Y,Z should always be capitalized. One of the sources has them as lower case.
2. when an unnamed parameter (arg_0) is used, this is equivalent to specifying Y or Z, whichever is dependent.
3. when Y or Z is used, this should be equivalent to using an unnamed parameter (arg_0).
4. when tabs are used to select Y and Z, the metadata describing the selected parameter is shown. (NetCDF always shows the dependent parameter).
5. The QDataSet read should use DEPEND_0 to have Y(X) and BUNDLE_1 for X,Y,Z.
6. Using X,Y,Z should give the same result as link(X,Y,Z).

Any differences should be noted here and in documentation.

[Jeremy Faden]

See also https://sourceforge.net/p/autoplot/bugs/2138/

[Jeremy Faden]

CDF uses lower case. I'm making it use upper case now, and lower case is still supported. I'll let the editor panel produce lower case URIs for a while to support old Autoplot versions.

[Jeremy Faden]

NetCDF also used lower case, and now uses upper case as well. I forgot to make sure the information about the selected data swaps out with the X,Y,Z selection.