ansible-oracle v1.5.1

Added 2 variables for enabling/disabling extra yum repositories:

- extrarepos_enabled
- extrarepos_disabled

Comma separated list of repositories that should be enabled/disabled.
e.g
If running a RHEL7 based AMI on aws, the following repos should be enabled for getting access to compat- packages

extrarepos_enabled: "rhui-REGION-rhel-server-extras,rhui-REGION-rhel-server-optional"