Changed linking order: -pthread -> back.

Otherwise error:
/usr/bin/ld: /usr/local/lib/libgflags.a(gflags.cc.o): undefined reference to symbol 'pthread_rwlock_wrlock@@GLIBC_2.2.5'
/lib/x86_64-linux-gnu/libpthread.so.0: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status

Makefile

@@ -165,12 +165,11 @@ ifneq ($(CPU_ONLY), 1)
 	LIBRARY_DIRS += $(CUDA_LIB_DIR)
 	LIBRARIES := cudart cublas curand
 endif
-LIBRARIES += pthread \
-	glog gflags protobuf leveldb snappy \
+LIBRARIES += glog gflags protobuf leveldb snappy \
 	lmdb \
 	boost_system \
 	hdf5_hl hdf5 \
-	opencv_core opencv_highgui opencv_imgproc
+	opencv_core opencv_highgui opencv_imgproc pthread
 PYTHON_LIBRARIES := boost_python python2.7
 WARNINGS := -Wall -Wno-sign-compare