Random local images

Re-rolled patch in #24 against 8.x-1.4.

And another Re-roll agains the latest version 1.6.

Here is a simple patch against 2.0.2

Thanks @CKIDOW, the patch works for me, albeit not with the private file system. Small price to pay, though, for the functionality.

Patch in #27 works well against 2.0.3 as well. I like the ability to customize the login images this way.

Thanks!

Updated patch #27 for 2.0.4

patch #30 worked for me (gin_login 2.0.4 on D core 10.2.5)