Documentation fixes to eliminate sphinx warnings

fix alma failure

# This is the 1st commit message:

add HiGal module

more cleanup

add changelog

it is possible for a cutout to be missing; we need to allow for that.
Also, the hack I had before isn't needed when you appropriately query
for multiple wavelengths

remove some comments, still not done with the PR

minor correction

added basic docs

pep8 fixes.  The bracket closures DO match the indentation, though.
pep8 lies sometimes.

add local tests and cleanup some testing

more interactive tests revealed that my hacks didn't really work, this
commit has some fixes

move everything into astroquery.herschel.higal

update relative paths

whitespace

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update tests

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the higal server genuinely isn't showing anything when I search online now

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add HiGal module

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more cleanup

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add changelog

# This is the commit message #7:

it is possible for a cutout to be missing; we need to allow for that.
Also, the hack I had before isn't needed when you appropriately query
for multiple wavelengths

# This is the commit message #8:

remove some comments, still not done with the PR

# This is the commit message #9:

minor correction

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added basic docs

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pep8 fixes.  The bracket closures DO match the indentation, though.
pep8 lies sometimes.

# This is the commit message #12:

add local tests and cleanup some testing

# This is the commit message #13:

more interactive tests revealed that my hacks didn't really work, this
commit has some fixes