APP_Framework/Framework/:update knowing framework

1.fix some Kconfig file
2.add tensorflow-lite-for-mcu in knowing file
3.add mnist application,note the application cannot be used with RAM less than 500K.
4.the version need to separate application and OS(rtt),later by using add transform layer to solve it.

APP_Framework/Framework/knowing/tensorflow-lite/Kconfig

@@ -0,0 +1,24 @@
+menuconfig USING_TENSORFLOWLITEMICRO
+    bool "Tensorflow Lite for Micro"
+    select RT_USING_CPLUSPLUS
+    default n
+
+if USING_TENSORFLOWLITEMICRO
+
+    choice
+        prompt "Select Tensorflow Lite Operators Type"
+        default USING_TENSORFLOWLITEMICRO_NORMAL
+
+        config USING_TENSORFLOWLITEMICRO_NORMAL
+            bool "Using Tensorflow Lite normal operations"
+
+        config USING_TENSORFLOWLITEMICRO_CMSISNN
+            bool "Using Tensorflow Lite CMSIS NN operations"
+    endchoice
+
+    config USING_TENSORFLOWLITEMICRO_DEMOAPP
+        bool "Using tensorflow lite for micro demo app"
+        default n
+
+endif
+