fix some algo weird hashrates (like blake)
and reset device between algos, for better accuracy
but this reset doesnt seems enough to bench all algos correctly...
to test on linux, could be a driver issue...
heavy: fix first alloc and indent with tabs...
reduce "false" warnings, and ignore unrelated/small ones <= 1 MB
On windows the gpu memory can be allocated by other processes
+ some cleanup in algos... (free/gpulog)