Better Visual Studio and Windows support.

[MaxDZ8]

For some reason this is compiled as C++ code in Visual Studio. A lot of changes involve safe casting from/to uints.

Fixed a typo in blake.c

Added plenty of missing .c files

cURL should really be an optional dependancy, as is SSL. Having it optional greatly simplifies compile: now one just has to download this, ptheads and hit go debug.

Arguably correct windows socket init & shutdown. jansson dependancy as vs reference instead of pragma, it seems other build systems would be better off specifying additional link.

Added missing lib, update to latest windows sdk.

Someone should really test yescrypt, in case someone is interested in GPU mining it (but WHY?).

[shtse8]

Any progress?