Clarify Gemfile to default to running on Fog release
Clarify Gemfile to default to running on Fog release

Our default position is to run against the version of
fog in vcloud-tools.gemspec. It should be rare that regular
users will need to run against an unreleased version.

Removing the comments that demonstrate how to do this,
in favour of preserving in this commit.

gds-operations/vcloud-edge_gateway,gds-operations/vcloud-edge_gateway,gds-operations/vcloud-edge_gateway