print udev rules before installing them/allow manual installation of rules

[solonovamax]

Currently, the process of installing the udev rules does not indicate what rules are to be installed nor does it allow the rules to be installed manually.

It would be great if it could do that, as I would much prefer to install the rules myself rather than having the script do it for me.

[solonovamax]

also, I will note that the udev rules are installed with the permissions set to 600. this permission level is quite unnecessary, and 644 should be quite fine.