Improved Definitions for Oracle Linux 6.4 and 5.9 x86_64

I know there are earlier pull requests (I am aware of #785 and #756) for Oracle Linux 5.9 and 6.4. I've checked both before sending the pull request.

Reason why I think my versions are better, see below.

Both definitions have been tested and validated.

## Improvements

#### Common (for both 5.9 and 6.4 x86_64)

`base.sh`

* uses the yum configuration files from Oracle's [**Public YUM Server**](http://public-yum.oracle.com/)
* uses RPM package to configure EPEL(https://fedoraproject.org/wiki/EPEL)
* breaks up long lines

`proxy.sh`

* For machines working behind firewalls

`chef.sh`

* uses the smart [script](https://www.opscode.com/chef/install.sh) from Opscode to determine distribution and find the best installation method. For Enterprise Linux and its derivatives, use the RPM packages.

* other code clean-ups and refactoring 

#### Oracle Linux 6.4 x86_64 specific

`puppet.sh`

* Use Puppet Labs YUM Repository to install puppet

#### Oracle Linux 5.9 x86_64 specific

`ruby.sh`

* improved the script, more flexible
* added LibYAML (compile from source to bypass warning)