New Slinkeserv and E-Z Learn versions

I've put a new slinke.exe installation on the website which features a new (documented!) version of E-Z Learn which allows the generation of 2-way device files. I've also changed slinkeserv a bit, mainly in appearance and DXS support. CDJ hasn't changed much in this version, so it's probably not necessary to install this version if you're just looking to update CDJ.