Run yum repolist to debug nightly install issues

Run yum repolist before setup.rb, after setup.rb (also before katello-installer)
and after katello-installer.
Merge pull request #63 from elyezer/nightly-repolist

Run yum repolist to debug nightly install issues
Add product install task

The product task makes easy to install every product distribution. If
needed it can create a virtual machine by specifying create_vm argument
is True. Also it can setup a DDNS entry if required environment
variables are set.

Rename install tasks to match the pattern <distribution>_install and use
better know distribution names.

Add aliases to ensure backward compatibility.
Add setup_vm_provisioning task

The task will setup all required packages and a network bridge device in
order to allow the target machine manage virtual machines using vm tasks.
Merge pull request #65 from elyezer/product-install-task

Add product install task
Merge pull request #66 from elyezer/provisioning-infra

Add setup_vm_provisioning task