using fog 1.19.0

this version contains changes around configuring storage_profile for vm
and creating/deleting org vdc networks
bumping up vcloud-tools version

because new version of fog is released which contains following changes.
fog1.19.0 contains changes around configuring storage_profile for vm
 and creating/deleting org vdc networks
Merge pull request #79 from alphagov/using_new_version_of_fog

using fog 1.19.0