remove THREAD_SAFE ifdefs. from now on, pthreads are required.

additionally we have some explicit init and deinit routines for
core.c now, so that we dont need to share variables with
libproxychains.c.

Makefile

@@ -17,7 +17,7 @@ SRCS = $(sort $(wildcard src/*.c))
 OBJS = $(SRCS:.c=.o)
 LOBJS = src/core.o src/common.o src/libproxychains.o src/shm.o src/allocator_thread.o src/ip_type.o
 
-CFLAGS  += -Wall -O0 -g -std=c99 -D_GNU_SOURCE -pipe -DTHREAD_SAFE
+CFLAGS  += -Wall -O0 -g -std=c99 -D_GNU_SOURCE -pipe
 LDFLAGS = -shared -fPIC -Wl,--no-as-needed -ldl -lpthread
 INC     = 
 PIC     = -fPIC