Generated a veewee configuration for creating a box for CentOS-6.3-x86_64-minimal.

Added sensu.sh to definitions/sensu-sandbox and modified definitions/sensu-sandbox/definitions.rb to include sensu.sh.

Also modified definitions/sensu-sandbox/cleanup.sh to remove the sensu repo.
Bugfix: Epel repo was not downloaded, thought it was already included by Veewee.
Added veewee and vagrant config files for a debian version of the sandbox.
The definition for sensu will be called now when installing the box.
Added the install script for sensu.