Adding disconnected mode fixes to hdp plugin

Changes
* Adding function to determine if package epel-release is installed
* Adding logic to determine if hadoop-swift integration package is
installed
* Changing behavior of provision_ambari to check for installed rpm if it
fails to download files from the internet
* Changing behavior of install_swift_integration to check for installed
rpm if it fails to download rpm from the internet
* Adding variable for epel-release name
* Adding variable hadoop-swift local rpm
* Removing -v -h from rpm command
* Adding --quiet to rpm command
* Adding a variable for yum command to install swift integration rpm
* Adding log messages for local fallbacks

Closes-Bug: #1320991
Closes-Bug: #1285133
Change-Id: I7fbbdf131fcee698684c39c7241bb919cd904e26
Merge "Adding disconnected mode fixes to hdp plugin"