XMR-Stak - reduced dev fee. Dev, stable and release builds for all CUDA versions

As a courtesy to the community, XMR-Stak is hereby offered in many different flavours.

https://prominertools.com/xmr-stak/

Builds are done for CPU + AMD + following CUDA versions:

8.0
9.0
9.1
9.2
10.0
10.1

Dev fee is reduced by 25%.

Every Github release, master or dev branch commit triggers a new build and the previous builds are archived, while still being available for download.