mount only if mount does not already exist

Signed-off-by: Thorsten Liebig <Thorsten.Liebig@gmx.de>
do lazy umount to prevent error/abort due to device busy

Signed-off-by: Thorsten Liebig <Thorsten.Liebig@gmx.de>
make getproot function it's own shell script; getchroot to only get chroots

Signed-off-by: Thorsten Liebig <Thorsten.Liebig@gmx.de>
fix: copy resolv.conf for initial download & extract as well

Signed-off-by: Thorsten Liebig <Thorsten.Liebig@gmx.de>
improved help text for getchroot

Signed-off-by: Thorsten Liebig <Thorsten.Liebig@gmx.de>
Merge pull request #3 from thliebig/master

A few improvments and one bug fix