fix CMake 

- remove all `"${VARNAME}` usages in if conditions
- increase cmake minimum version to 3.1 to have the new behavior of [CMP0054](https://cmake.org/cmake/help/v3.1/policy/CMP0054.html)

- fix wrong compare for HWLOC not found
- remove usage of microhttpd variable if microhttpd is disabled

Adding Dockerfile and fixing build_xmr-stak_docker script

Fixed incorrect Releases URL in README.md#Download

fix CUDA launch bounds usage

fix auto suggestion for low end devices 

fix #191

lauch bounds must be placed before the return type but after the template paramater

Add compilation instructions for MacOS

Fix for AMD GPU detection on MacOS X

update windows compile guide  

add missing nvidia help to usage.md

add NVIDIA cli options to the help message

Update gpu.hpp

Fix indent on hash rate report.

Fix for AMD GPU detection on MacOS X
On MacOS X the platform is reported as Apple, and the vendor is reported as AMD.

Fix crash on FreeBSD (#177)

Fixing the compile error on MacOS X

Fix uninitialized memory accces

fix appvoyer

Uninitialized memory access is UB in C/C++, fix it.

This change fix #177 and compiler warning too.

add explicit note that VSC v141 must be used for AMD and CPU compile.

Increase bfactor for all devices with lesser than 6 multi processors.

Remove the execution of the binary at the end of the CI test. This is only currently a temporary solution.

Add cheksums

Add cheksums

Add windows exit

Add windows exit

update windoes compile guide

Point to new xmr-stak-dep precompiled binaries if CUDA9 is used.

fix windows compile documentation

fix broken windows compile with v140

- add copy of openssl libs to appvoyer CI tests
- update windows compile documentation

add microhttpd libs explicit to `xmr-stak-c`