Add a virtualmin-install.log file to aid debugging

log4sh looks like an excellent logging library for Bourne shells (not just bash):

http://forestent.com/projects/log4sh/

Size might be a concern, though I can drop it into the virtualmin lib repository to keep it out of the install.sh script itself (which is already too big and needs to start shaking out into libs of its own).

Status: 
Closed (fixed)