Update blechat.py to be useful as a show demo.

Pull connect to menu into separate function
Add a couple special words

blechat.py

@@ -37,6 +37,12 @@ class BleChat:
         self.lcd.show()
         self.led.off()
 
+    def _connect_message(self):
+        self.clear_lcd()
+        self.lcd.write('Connect to:\n')
+        self.lcd.write('{}\n'.format(self.name))
+        self.lcd.write('{}\n'.format(self.local_mac[0:17]))
+
     def clear_lcd(self):
         for i in range(0, 4):
             i += 1
@@ -45,12 +51,9 @@ class BleChat:
         self.lcd.show()
         pyb.delay(50)
 
-    def start(self):
+    def start(self, demo=False):
         print("Waiting for connection...")
-        self.clear_lcd()
-        self.lcd.write('Connect to:\n')
-        self.lcd.write('{}\n'.format(self.name))
-        self.lcd.write('{}\n'.format(self.local_mac[0:17]))
+        self._connect_message()
         done = False
         while not done:
             event = self.rs.get_event()
@@ -70,9 +73,16 @@ class BleChat:
             elif event == self.rs.DISCONNECT_EVENT:
                 print('Disconnected')
                 print('Remote Device State = {}'.format(self.rs.get_device_status()))
-                self.clear_lcd()
-                self.lcd.write('Device\nDisconnected,\nPlease Reset\nCutiPy')
-                done = True
+                if demo:
+                    self.clear_lcd()
+                    self.lcd.write('Device\nDisconnected\n')
+                    self.rs.advertise(True)
+                    pyb.delay(100)
+                    self._connect_message()
+                else:
+                    self.clear_lcd()
+                    self.lcd.write('Device\nDisconnected,\nPlease Reset\nCutiPy')
+                    done = True
             elif event == self.rs.WRITE_EVENT:
                 event_rsp = self.rs.get_event_data(event)
                 print('Write event')
@@ -83,7 +93,14 @@ class BleChat:
                     else:
                         self.led.on()
                 else:
-                    self.lcd.write(event_rsp[0] + '\n')
+                    if event_rsp[0] == 'clear':
+                        self.clear_lcd()
+                    elif event_rsp[0] == 'exit':
+                        self.clear_lcd()
+                        self.lcd.write('App Exited,\nPlease Reset\nCutiPy')
+                        done = True
+                    else:
+                        self.lcd.write(event_rsp[0] + '\n')
 
                 # event_attr_index = rs.event_attr_hiandle()
                 # if event_attr_index == write_attr_ index: