moved multi_threaded to separate dir

examples/multi_threaded_server/Makefile

+# Copyright (c) 2014 Cesanta Software
+# All rights reserved
+
+PROG = multi_threaded_server
+CFLAGS = -W -Wall -I../.. -g -O0 $(CFLAGS_EXTRA)
+SOURCES = $(PROG).c ../../mongoose.c
+
+$(PROG): $(SOURCES)
+	$(CC) -o $(PROG) $(SOURCES) $(CFLAGS)
+
+clean:
+	rm -rf $(PROG) *.exe *.dSYM *.obj *.exp .*o *.lib