Add makefile to build complete SDK install.

Makefile

@@ -0,0 +1,58 @@
+TOP=$(PWD)
+TOOLCHAIN=$(TOP)/toolchain
+
+all: sdk_patch $(TOOLCHAIN)/lib/libhal.a $(TOOLCHAIN)/bin/xtensa-lx106-elf-gcc
+	@echo
+	@echo "Xtensa toolchain is built, to use it:"
+	@echo
+	@echo 'export PATH=$(TOOLCHAIN)/bin:$$PATH'
+	@echo
+	@echo "Espressif ESP8266 SDK is installed, to use it run compiler as follows:"
+	@echo
+	@echo "xtensa-lx106-elf-gcc -I$(TOP)/sdk/include -L$(TOP)/sdk/lib"
+	@echo
+
+sdk_patch: sdk/lib/libpp.a
+
+sdk/lib/libpp.a: esp_iot_sdk_v0.9.2/.dir FRM_ERR_PATCH.rar
+	unrar x -o+ FRM_ERR_PATCH.rar
+	cp FRM_ERR_PATCH/*.a $$(dirname $@)
+
+FRM_ERR_PATCH.rar:
+	wget --content-disposition "http://bbs.espressif.com/download/file.php?id=10"
+
+esp_iot_sdk_v0.9.2/.dir: esp_iot_sdk_v0.9.2_14_10_24.zip
+	unzip $^
+	ln -s $$(dirname $@) sdk
+	touch $@
+
+esp_iot_sdk_v0.9.2_14_10_24.zip:
+	wget --content-disposition "http://bbs.espressif.com/download/file.php?id=9"
+
+$(TOOLCHAIN)/lib/libhal.a: $(TOOLCHAIN)/bin/xtensa-lx106-elf-gcc
+	make -C lx106-hal -f ../Makefile libhal
+
+libhal:
+	autoreconf -i
+	PATH=$(TOOLCHAIN)/bin:$(PATH) ./configure --host=xtensa-lx106-elf --prefix=$(TOOLCHAIN)
+	PATH=$(TOOLCHAIN)/bin:$(PATH) make
+	PATH=$(TOOLCHAIN)/bin:$(PATH) make install
+
+
+$(TOOLCHAIN)/bin/xtensa-lx106-elf-gcc: crosstool-NG/ct-ng
+	make -C crosstool-NG -f ../Makefile toolchain
+
+toolchain:
+	./ct-ng xtensa-lx106-elf
+	sed -r -i.org s%CT_PREFIX_DIR=.*%CT_PREFIX_DIR="$(TOOLCHAIN)"% .config
+	sed -r -i s%CT_INSTALL_DIR_RO=y%"#"CT_INSTALL_DIR_RO=y% .config
+	./ct-ng build
+
+crosstool-NG/ct-ng:
+	make -C crosstool-NG -f ../Makefile ct-ng
+
+ct-ng:
+	./bootstrap
+	./configure --prefix=`pwd`
+	make MAKELEVEL=0
+	make install MAKELEVEL=0