Enable remote repos at a lower priority

This will enable the yum repos at a lower priority than the
  local cache repo.
Also removed some old bluez-utils stuff we don't use/need.
add telnet to cached packages
install telnet at bootstrap
Merge pull request #169 from casharma/install/telnet

Install/telnet
Merge pull request #168 from casharma/add/yum-priorities

Enable remote repos at a lower priority
TRAINVM-47: do not check for updates
Merge pull request #170 from casharma/bugfix/TRAINVM-47

TRAINVM-47: do not check for updates
Adding vagrant dependency to intial setup instructions.
Add basic error checking of vmos and vmtype command-line arguments.

Quick pair of conditionals at the start, to abort the rake task if
either the vmos or the vmtype arguments are not ones we can use.
Updating tar.gz download URL to include version-specific subdirectory.
Merge pull request #175 from fnaard/ticket/TRAINVM-50/add_subdirectory_to_pe_url

Updating tar.gz download URL to include version-specific subdirectory.
Adding screen and zsh to base install.
Merge pull request #176 from fnaard/ticket/TRAINVM-37/add_screen_zsh_packages_to_bootstrap

Adding screen and zsh to base install.
Merge pull request #172 from fnaard/add_vagrant_to_initial_setup

Adding vagrant dependency to intial setup instructions.
Merge pull request #173 from fnaard/add_validation_of_vmos_and_vmtype

Add basic error checking of vmos and vmtype command-line arguments.

TODO: check other ENV vars, such as (release | latest) for PESTATUS etc.
Updating vmos and vmtype validation to ignore when they're null.
Merge pull request #177 from fnaard/do_not_validate_null_vmos_or_vmtype

Updating vmos and vmtype validation to ignore when they're null.
Fixing typo in %post to use /bin/true.
Merge pull request #178 from fnaard/ticket/TRAINVM-52/fix_kickstart_path_for_bin_true

Fixing typo in %post to use /bin/true.
Fix spelling error.