Use vCloud Tools Tester

This commit just adds it to the gemspec and the two integration tests (not the `spec_helper` as that is used in the unit tests as well and this is not required there.
Change vdc variable names for consistency

`vdc_name_1` to `vdc_1_name`
`vdc_name_2` to `vdc_2_name`

This is what we do with, for example, networks, and also other references, e.g. `vdc_1_storage_profile_href`. It also makes sense - it's the names of two VDCs, not the two names of a VDC.
Change network parameter names for consistency

e.g. from `network1_ip` to `network_1_ip`, for consistency with other parameter names.

This commit also bumps the version of vCloud Tools Tester required - it's not necessary at this stage as this is not yet using vCloud Tools Tester, but the reason for requiring that version will be that is the version that includes the updated network names so committing this here for clarity.
No need for duplicate VDC_NAME env vars

This is duplicated in the testing config for every environment, so removing the need for one of them. Strictly speaking, this change is not required because I'm about to remove the need for any of these environment variables, but committing it so it's clear when and why it disappeared.
Add template for the testing parameters & doc

This commit also adds the actual parameters file to `.gitignore` (to join quite a lot of cruft! A story for another day). The idea is that you copy the template file and put your actual parameters in there, so no danger of committing your environment details accidentally. As explained in the documentation.

This commit doesn't remove the environment variables documentation from the README as at this point, that is still how the integration tests are run.
Use vCloud Tools Tester to get parameters

This changes the way you run the tests (see the README change) but means that all tests can be run using a config file that we can share. It also means the only environment variable we need to set it is the FOG_CREDENTIAL so that removes the issue of parameters from one test interacting with those from another, and it also makes explicit the test parameters we are using.
Update Jenkins files to get parameters from GHE

At the moment the Jenkins jobs export a ton of environment variables which are then used in the tests. After the change to use vCloud Tools Tester is merged, the tests will be expecting input from a config yaml file.

This change clones the repository in which I have saved the config file we can use, copies the file to the correct place and then removes the repository. The removal is because although most of our Jenkins jobs have 'Delete workspace before build starts' checked, I would prefer to rely as little as possible on Jenkins config.

Having said that, this change requires that the Jenkins jobs, as well as exporting the variables required for the fog credentials, now need to export FOG_CREDENTIAL=[the name of the config block in the config file]. I have added that to both the vCloud Launcher Jenkins jobs. Should we add it to `tools/fog_credentials` instead?

This will need updating when we address https://www.pivotaltracker.com/story/show/71594524
Clean workspace before starting

Deleting the Gemfile.lock will mean jenkins has to resolve all dependencies again which is good from a testing perspective. In any case, we have the option Jenkins option 'Delete workspace before build starts' checked. This is just to make this explicit in code so that we don't depend on config in Jenkins.

Git clean removes untracked files - for the same reason above. Putting this also means we no longer need to explicitly remove the checked out config directory.
Update README with new integration testing details
Merge pull request #26 from alphagov/use-vcloud-tools-tester

[#65363454] Use vcloud tools tester