[ovirt] elide passwords in {iso,image}uploader.conf

These two configuration files may contain passwords of the form:

Add do_file_sub() calls to the plugin's postproc to remove these.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>
[ovirt] elide passwords in logcollector.conf

This configuration file may contain passwords of the form:

And:

Add these to the existing 'passwd_files' processing added in
commit 3da5697.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>