Added permission tests framework for api
flake 8
flake8 travis
activation-key tests related to env and content-view
test to update CV of selected activation-key
added support to associate product with selected key
suresh comments
implemented test 'test_associate_product_2'
elyezer comments
travis complaints
added an exception and replaced hard-coded comment with var
Product label cannot be edited after creation.

Once cannot edit a product label after its creation, so I'm deleting one
specific test for Products via CLI.
updated assertions as per review comments
Added simple api test to create content view
fixed the travis issue
fixed the cli/api issue
Merge pull request #724 from sghai/ak-test

Activation key tests
Merge pull request #735 from omaciel/cannot-edit-product-label

Product label cannot be edited after creation.
Added publish, promote, version and updated the construct_command for version
The system command is now content-host.

Due to the changes introduced by
https://github.com/Katello/hammer-cli-katello/pull/145, the CLI command
``system`` has been renamed to ``content-host``. This only affects the
CLI.