Improvements to the flame_wave flame front analysis scripts

[yut23]

PR summary

front_tracker.py

• dataset processing can run in parallel
• added code to make interactive plots of each dataset that show the raw slice data, the averaged profile, and the positions for each metric
• metric thresholds are calculated using both the local maximum and global maximum at the same time (under <field>[<fac>%] and <field>[<fac>%]_gmax, respectively)
• the local maximum for each field is stored in the output file, in the max_<field> column
• if a field value never goes below the threshold for a metric, its position will be stored as NaN
• --[xyz]lim arguments now work, despite some yt bugs
• allow ignoring plotfiles after a certain time with --tmax
• default FRB resolution is set to match the finest level, and is automatically adjusted if custom limits are used

flame_speed.py

Now takes min and max times for the linear regression as optional arguments, and can plot multiple metrics at the same time.

PR checklist

• test suite needs to be run on this PR
• this PR will change answers in the test suite to more than roundoff level
• all newly-added functions have docstrings as per the coding conventions
• the CHANGES file has been updated, if appropriate
• if appropriate, this change is described in the docs

[yut23]

Screenshot of the interactive plots:

[yut23]

The missing checks might be because I opened this PR against main initially. I just ran codespell locally, and it didn't find anything.

[zingale]

I'm fine with it. You can merge if you want.