Minidump crashpad integration documentation

When I integrate the crashpad code into my application according to then a http status 400 is returned.
I had to add the""–no-upload-gzip" to the list of arguments to get a successful upload of the minidump files.

Could this be added to the documentation?

Definitely on our TODO, but we should probably escalate that so no one else gets it wrong.

/cc @mitsuhiko @jauer