Add examples to aca_l0 docstrings
Add examples to docs in asp_l1

Add docstring for get_files()
Add docstrings and examples to obspar
Add docstrings to aca_hdr3
Add MSID description text to hdr3 objects
Improve MSID attr passing in aca_hdr3
Fix bug in hdr3 data masking
Use object config for data_root in get_files()

Instead of passing it as an option.
Add logic to get_files by obsid or time range
Sort get_files output by tstart
Add aca_l0 and asp_l1 get_files to docs
Combine module docs in one api page
Remove individual module docs
Copy module examples to top level docs