Additional test_git scenarios

Includes coverage for accept_hostkey and additional scm URL formats.
Add credentials.template and support custom INVENTORY

Testers may override the inventory and vars-file using the environment
variables 'INVENTORY' and 'VARS_FILE'.
Fixes for run_command shell usage in remainder of packaging modules, save portinstall.
Only use cwd in run_command kwargs if the directory exists
Some more run_command updates.
Fix typo in portinstall
Fix missing colons in cpanm
More shell updates
Close parens in portinstall
More shell fixes
Fixup shell handling in monit module.
Still more shell fixes.
Merge pull request #6453 from jlaska/test_git

Additional test scenarios in roles/test_git
Correct test integration ec2 cleanup script
Fixes various typos introduced in a9017af2bb648930e27bab52de12f9983411778c.
Fixes odd encoding problem with wait_for_service.
Fix regression in dnsmadeeasy module caused by fetch_url change

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
Merge pull request #6460 from jsmartin/riak-bugfix

Fixes various typos, fetch_url now working, changed command composure for wait_for_service
Shell updates.
mysql_db module: typo fix

Tests clean.
Merge pull request #6461 from risaacson/modules_make_run_command_safer

Modules make run command safer