Pre-RC updates

[aburrell]

Description

Addresses #1155 by comparing the package documents and tests to the ecosystem templates. Also:

• Improves file handling in the package init,
• Fixes call to importlib's metadata,
• Updates the package citation, and
• Removes and old TODO statement

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

How Has This Been Tested?

Ran unit tests locally. Also:

import pysat

pinst = pysat.Instrument('pysat', 'testing')
xinst = pysat.Instrument('pysat', 'ndtesting')
minst = pysat.Instrument('pysat', 'testmodel')
pinst.load(yr=2009, doy=1)
xinst.load(yr=2009, doy=1)
minst.load(yr=2009, doy=1)

# Printing 'longitude' for each instrument will show the range is 0-360. Change that
pysat.utils.coords.update_longitude(pinst, 'longitude')
pysat.utils.coords.update_longitude(xinst, 'longitude')
pysat.utils.coords.update_longitude(minst, 'longitude')

# Now -180-180
print(pinst['longitude'])
print(xinst['longitude'])
print(minst['longitude'])

Test Configuration:

• Operating system: OS X Big Sur
• Version number: Python 3.9
• Any details about your local setup that are relevant

Checklist:

• Make sure you are merging into the develop (not main) branch
• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• Add a note to CHANGELOG.md, summarizing the changes

If this is a release PR, replace the first item of the above checklist with the release
checklist on the wiki: https://github.com/pysat/pysat/wiki/Checklist-for-Release