Added project support to GCS through LibCloud

[slightfoot]

Please see the docs here for reference to this paremter.
https://libcloud.readthedocs.io/en/latest/compute/drivers/gce.html

Perhaps the docs should be updated to reflect this.

[codecov-io]

Codecov Report

Merging #269 into master will decrease coverage by -0.07%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master     #269      +/-   ##
==========================================
- Coverage   59.32%   59.25%   -0.07%     
==========================================
  Files          17       17              
  Lines        1694     1696       +2     
==========================================
  Hits         1005     1005              
- Misses        689      691       +2

Impacted Files	Coverage Δ
storages/backends/apache_libcloud.py	0% <ø> (ø)	✅

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[jschneier]

The project is optional (will default otherwise) but probably good to have the option.

[slightfoot]

@jschneier thanks for the merge. libcloud docs mentioned above refer to this parameter as required, but you probably know better.

Just looking at my commit it might be better to use the provider as the extra_kwargs default value. This would allow for optional parameters to be passed across from provider config to drivers.

[jschneier]

Yeah I agree. What we currently have can only lead to madness.