Documentation updates

This allows the use of an args list with leading environment variables,
which otherwise would fail due to the way Popen works.

This reverts commit 4273cb2d.

This allows the use of an args list with leading environment variables,
which otherwise would fail due to the way Popen works.

To support parallel cloud test execution, create and provide a random string to
cloud integration tests.  The variable 'resource_prefix' can be used in cloud
roles and during resource cleanup to safely create/destroy cloud-based
resources.

Additional changes include:

 * The roles test_ec2_key and test_ec2_group were updated to use to
 {{resource_prefix}}.

 * Additionally, the Makefile was updated to set resource_prefix to a random
 string.  The Makefile will also use 'resource_prefix' during cloud_cleanup.

 * All test_ec2* roles were updated to add 'setup_ec2' as a role dependency.

This reverts commit 3cd7d47b.

Modules make run command safer

Tests clean.

Fixes various typos, fetch_url now working, changed command composure for wait_for_service

Also:
* changed this module to use https for requests to the API
* fixed a bug in which a traceback was caused when the domain wasn't found

Fixes #6457

Fixes odd encoding problem with wait_for_service.

Additional test scenarios in roles/test_git

Testers may override the inventory and vars-file using the environment
variables 'INVENTORY' and 'VARS_FILE'.

Includes coverage for accept_hostkey and additional scm URL formats.

git: Execute git commands in `dest` directory