Add reboot required notification for cmdlets that require it

[mikenelson-io]

Some, if not all (I have not tested all of them) of the changes made by the cmdlets do require a reboot or a restart of Explorer to take effect.

[mikenelson-io]

Ties into Issue #8, however, not all instances of restarting Explorer.exe will work, whereas a reboot surely will.

[jaapbrasser]

Indeed, good idea, have you noticed any cmdlets in particular that require it.

Although I guess I'll have to go over all over them after I get the restart explorer built-in.