Always replace the bash and zsh rc files.

Sourcing the .custom(bash|zsh)rc file should allow people to customize
their configuration while allowing us to constantly maintain the files
we need in order to set up the ruby primer.
Updating the bashrc to mention that the file is managed.
Add a managed warning to the zshrc file.
Added simple versioning

This uses a `version.yaml` file to keep track of major/minor versions. I
started this wilth major of 2, because this is the second major iteration
of the build process. I expect that we'll bump that to 3 when we switch
to Packer. The minor version of 1 was arbitrary.

The `/etc/puppetlabs-version` file will contain a version of _[Testing
Build]_ unless the VM is built with the `release` task, which will
automatically increment the minor version and commit it.

Each classroom verification script will now output a version string. My
intent is to add the expected version number to the courseware exercise
guides to keep us honest with our VM release schedule.

This PR is not completely tested due to the difficulty in unit testing
the build process. Please test and tweak as appropriate before merging.
fixed a variable name
strip the build number
Merge pull request #215 from binford2k/feature/versioning

Added simple versioning
Merge pull request #210 from klynton/fix-userprefs-2

Always replace the bash and zsh rc files.

I'm going to merge this and then refactor how the files are sourced.
Move customizations into puppet scripts

This allows students to customize their environments as they see fit;
even to the point of completely turning off our pretty prompt stuff and
all, should they desire.
Add the libjpeg-turbo package for 3.2
Actually manage the updates repo
Merge pull request #217 from binford2k/fix/3.2/libjpeg

Add the libjpeg-turbo package for 3.2

Thank you @binford2k
Merge pull request #216 from binford2k/wip/customizable_user_environment

Move customizations into puppet scripts
Bump module version
Fixes parameter to be array

Addresses #TRAINVM-62

Maybe not a complete fix, so I'm not closing the ticket. We'll observe
it in the wild for a bit and see how things go.
Merge pull request #219 from binford2k/ticket/TRAINVM-62/time_servers_should_be_array

Ticket/trainvm 62/time servers should be array
Update README

Document ENV vars with examples.
Update README.markdown
Merge pull request #220 from casharma/update-readme

Update README
change some Debian stuff to Ubuntu stuff