Switch from relative to absolute imports

[xylar]

This is the recommended python philosophy: "explicit is better than implicit".

[xylar]

This follows from: #280 (comment)

[xylar]

Testing

I ran the QU240 test case I always use on my laptop. Once I got all the absolute imports right, everything worked as expected.

[xylar]

@jhkennedy, I would suggest two tests if you are willing to review this PR:

1. run the analysis on one of the NERSC simulations we use, which entails:
   a. copy a config file in configs/edison/config.* .
   b. edit the config file to give a output directory (typically on $SCRATCH or $CSCRATCH, but you can't use an environment variable name).
   c. run the analysis: ./run_mpas_analysis --purge config.<run_name>. (The --purge flag is optional but I find it useful in case you need to run more than once or you want to reuse the same scratch location as you've used in the past.)
2. do some kind of a search through the code to make sure I didn't miss any relative imports. I think I got them, but a second set of eyes would be useful.

Thanks!

[jhkennedy]

@xylar Happy to! I'll put it on my schedule for tomorrow.

[jhkennedy]

Everything, except two very small changes, looks good to me here!

Unfortunately, I'm not a member of the acme group on Edison, so I had to run the tests on Titan. Other than a few errors from missing files (which look correct and not caused by this PR) everything ran smoothly and output the expected website.

The changes are just small formatting changes -- there are a couple of from import statements that have two spaces.

[jhkennedy]

There are two spaces here after the from

[jhkennedy]

There are two spaces here after the from

[xylar]

@jhkennedy, I’ve fixed the two formatting issues you found (thanks!). Let me know if there’s anything else before I merge.

[jhkennedy]

Looks good to me; merge on!

[xylar]

Thanks, @jhkennedy.