Information about mms credentials

[xandrd]

MMS loading routines create a login file mms_auth_info.pkl in the user's home folder. However, I did not find any documentation about this. Also, the mms login function mms_login_lasp has insufficient documentation. As the results I was getting an error due to previously created pkl file. The user variable was assigned to None and broke the code on concatenation of the strings:

pyspedas/pyspedas/mms/mms_login_lasp.py

Line 65 in 97f7ad5

logging.error('Invalid password for user: ' + user + '; trying public access..')

Note, it was not resulted an authentication error, as should, but broke the code within the logging system.

The issue was resolved when I deleted pkl file, but I had to dig though the code to find the error.

Suggested actions:

• Extend documentation for mms_login_lasp
• Modify mms.rst documentation files explaining how MMS login system work.
• Add guide on how to fix the login issue (e.g., delete pkl file)