Add support for MODIS level 2 cloud products

[simonrp84]

This PR adds support for a subset of datasets contained in the MODIS level 2 cloud products (types MOD06 and MYD06). No code changes, just a new file pattern in the YAML and some new dataset names.

[coveralls]

Coverage increased (+0.003%) to 89.624% when pulling 603fc1d on simonrp84:MxD06 into cf9aab4 on pytroll:master.

[codecov]

Codecov Report

Merging #1200 into master will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1200   +/-   ##
=======================================
  Coverage   89.62%   89.62%           
=======================================
  Files         200      200           
  Lines       29550    29550           
=======================================
+ Hits        26483    26484    +1     
+ Misses       3067     3066    -1     

Impacted Files	Coverage Δ
satpy/scene.py	90.22% <0.00%> (+0.17%)	⬆️

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[mraspaud]

Thanks for this PR! is there any overlap with #812 ?

[simonrp84]

Thanks for this PR! is there any overlap with #812 ?

Aaah, I hadn't seen that PR. Yes, as far as I can see everything in my PR is also included in that PR. Do we have a timeline or anything still pending on #812 ? Would be great to have it integrated!

[mraspaud]

I'm rereviewing it now