Don't rely on apt-get to install debootstrap. debootstrap scripts can be downloaded and run on all distributions with this method of finding the latest tar, and extracting it.

Now the builders can run on all Linux systems. Not just Debian based ones, and now only touches the ISO files it extracts, and subfolders of the build folder. (and nothing in /usr or /var by installing new packages anymore)

git-svn-id: https://rebeccablackos.svn.sourceforge.net/svnroot/rebeccablackos@2507 56e3d1a8-0179-4092-b3e2-9fbbcda0c0a9
exit the main builder script if debootstrap doesn't download

git-svn-id: https://rebeccablackos.svn.sourceforge.net/svnroot/rebeccablackos@2508 56e3d1a8-0179-4092-b3e2-9fbbcda0c0a9