Point to working links for debian images
Work in progress to rewrite systemvm box definition in clean code.

* Refactor build.sh to use functions and pretty logging.
* Add a new test.sh which tries several different build.sh invocations.
* Add a new 'debianbase' definition which is just the basic debian box (no systemvm functionality). This is used for testing.
* Add a new 'newsystemvm' definition which is a work-in-progress replacement of the 'systemvmtemplate' definition:
** reduce duplication between preseed.cfg and postinstall.sh
** remove duplication between postinstall.sh and cloud-scripts
** install cloud-scripts from current working copy instead of tying to a download of the apache master branch
** split up postinstall.sh into small utility scripts and clean up that code
** clean up preseed.cfg to match current veewee/debian best practices and remove cruft