Bugfix: SGW: Pass actual cgpu_info to prune_worklog_thread instead of silently casting one from getwork_client
configure: Display getwork proxy server support in summary
SGW: For Windows builds, include winsock2.h instead of POSIX networking headers
Bugfix: make-release: Include libplibc-1.dll if available
make-release: Only try to include libmicrohttpd if bfgminer.exe depends on it
Merge branch 'httpsrv' into bfgminer

Conflicts:
	make-release