Updated Readmes for demos

Author: mateoconlechuga

CEdev/examples/library_examples/keypad/demo_2/readme.md

@@ -1,3 +1,3 @@
-# Demo 1
+# Demo 2
 
-This demo shows how to interpret multiple keypresses at the same time
+This demo waits for the enter, clear, or on key to be pressed using interrupts

CEdev/examples/library_examples/keypad/demo_3/readme.md

@@ -1,3 +1,3 @@
-# Demo 1
+# Demo 3
 
-This demo shows how to interpret multiple keypresses at the same time
+This demo changes the color of the screen while any key is being held. It uses interrupts and the on interrupt to exit.