Change the unit of electron density from m-3 to cm-3 following model naming convention

[huishao-r]

Description

electron density unit should be cm^-3, instead of m^-3, since the model geoval unit will be cm^-3. Here is the Model geoval naming convention

Issue(s) addressed

This change will ensure the same unit implemented for electron density observed values, geoval values and h(x) values.

Dependencies

Impact

converted ionosonde obs files will be updated with new unit and values.

Checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have run the unit tests before creating the PR

[BenjaminRuston]

@huishao-r a file got added with ^M at the end of every line!

and seemed like it was maybe from git? anyway fixed it and added conversion to density_conf as well

[BenjaminRuston]

this does the conversion to number per cubic centimeter, which isn't SI but apparently follows model conventions