[google] Don't swallow google errors in images.get

Catch and raise only Fog::Errors::NotFound
Fix mock, images.get now returns a 404 if image does not exist
[Brightbox] Round out fog-brightbox gem

Adding Gemfile, Rakefile, README and licence information.
[Brightbox] Use minitest in Brightbox module

Includes a simple test of Compute class.
Merge pull request #2745 from maestrodev/google-image-notfound

[google|compute] Don't swallow google errors in images.get
[DigitalOcean] Skip consistently timing out tests

The server tests in digital ocean have been frequently timing out.

* https://travis-ci.org/fog/fog/jobs/20605301#L1030
* https://travis-ci.org/fog/fog/jobs/19765753#L1233
...and many more

Each timeout run wastes Travis resources and the time of the people who
have to check why their unrelated changes are failed.

We've even become so complacent about it, standard practice is to just
comment and merge.

So I'm disabling the tests until someone fixes it or we replace the
server tests with a cleaner approach, whichever comes first.
set custom application/version for google compute
[rackspace|compute_v2] removing hard coded timeout in servers
use custom and fog user agent
Merge pull request #2753 from fog/disable_digital_ocean_test_fail

[DigitalOcean] Skip consistently timing out tests
bump rbovirt dependency
Merge pull request #2756 from rackspace/remove_timeout

[rackspace|compute_v2] removing hard coded timeout in servers
Merge pull request #2754 from erjohnso/google-ua

[google|compute] Allow seting custom application/version for requests
Merge pull request #2752 from brightbox/brightbox_module_updates

[Brightbox] Updates for gem/module