SendData.c: fix for winsock2

Must call WSAStartup() before using a socket under winsock
Version 2.2 was released in 1997, safe to assume we can use it instead.
Initial Clang fixes

-Wundef fix in TuxDef.h
-Wshadow in MR.c, size was already used
-Wdocumentation in ErrCodes.c
CM.c: pointer arithmetic on void* is a GNU extension
More Clang fixes

SendData.h: add extern for -Wmissing-variable-declarations
ErrCodes.c/h: format string for LogCip() should be const
AB.h: add missing enumerations