Use external handlers in tizenrt-artik05x target (#1822)

This patch includes followings:
- Use external handlers in jerry-ext.
- Make jerry_main similar to other ports. (including options)
- Merge jerry_port.c into jerry_main.c
  jerry_port is clearly out of jerry-core.

This patch not included following:
- Use jerry-libm, instead of system libm.
  It is already included.
  We choose to use jerry-libm since the result of cube-3d sunspider was inaccurate
  when using NuttX libm.
- Correct setjmp/longjmp implementation.
  I tried to bring the source from NuttX port.
  Unfortunately it does not work in tizenrt-artik05x as it is.
  I will take a closer look the code and make sure it works.

JerryScript-DCO-1.0-Signed-off-by: Sanggyu Lee sg5.lee@samsung.com

targets/tizenrt-artik05x/Makefile.tizenrt

@@ -12,10 +12,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-CURDIR		= `pwd`
 JERRYHEAP	?= 16
-BUILD_DIR	?= build/tizenrt-artik05x/
-LIBTARGET_DIR	?= ../tizenrt/build/output/libraries
+BUILD_DIR	?= build/tizenrt-artik05x
+LIBTARGET_DIR	?= $(abspath $(PWD)/../tizenrt/build/output/libraries)
 
 EXT_CFLAGS += -mcpu=cortex-r4 -mfpu=vfpv3
 EXT_CFLAGS += -fno-builtin -fno-strict-aliasing
@@ -46,10 +45,10 @@ libjerry:
 	 -DMEM_HEAP_SIZE_KB=$(JERRYHEAP) \
 	 -DCMAKE_BUILD_TYPE=Release
 
-	make -C$(BUILD_DIR) jerry-core
-	make -C$(BUILD_DIR) jerry-libm
+	make -C$(BUILD_DIR) jerry-core jerry-libm jerry-ext
 	cp $(BUILD_DIR)/lib/libjerry-core.a $(LIBTARGET_DIR)
 	cp $(BUILD_DIR)/lib/libjerry-libm.a $(LIBTARGET_DIR)
+	cp $(BUILD_DIR)/lib/libjerry-ext.a $(LIBTARGET_DIR)
 
 clean:
 	rm -rf $(BUILD_DIR)