Fix Issue 904

This commit adds the ability for a user to set the VNC password.
If the password is not set one will be set for you. This is done
to address a potential security issue with not having password
protected VNC access by default.

Issue:
https://github.com/rcbops/chef-cookbooks/issues/904
Merge pull request #403 from cloudnull/issue904

Merged automatically by jenkins after successful build test
Fix for issue 915

The xvpvncproxy is not equally supported on RHEL and Ubuntu alike,
so this fixes the issues in our cookbooks with the missing package
in RHEL by removing it from our cookbooks.  It no longer makes sense
to support the installation and monitoring of the installation of
xvpvnc when it the package is not supported on both RHEL and Ubuntu.

Issue:
https://github.com/rcbops/chef-cookbooks/issues/915
Merge pull request #404 from cloudnull/issue915

Merged automatically by jenkins after successful build test