Ad-Hoc Commands, Various bug Fixes and Smaller Improvements

• Fixed an issue where the settings file could be world readable
• Added the ability to associate a project with an organization
• Added setting "verify_ssl" to disallow insecure connections
• Added support for additional cloud credentials
• Exposed additional options for a cloud inventory source
• Combined " launch-time extra_vars" with " job_template extra_vars"
  for older Tower versions
• Changed the extra_vars parameters to align with Ansible parameter
  handling
• Added the ability to run ad hoc commands
• Included more detail when displaying job information
• Added an example bash script to demonstrate tower-cli usage