Adding all the messages into API docs. #3

Author: Kevin J Walters

docs/api.rst

@@ -6,3 +6,40 @@
 
 .. automodule:: adafruit_midi
    :members:
+
+.. automodule:: adafruit_midi.channel_pressure
+      :members:
+
+.. automodule:: adafruit_midi.control_change
+      :members:
+
+.. automodule:: adafruit_midi.midi_message
+      :members:
+
+.. automodule:: adafruit_midi.note_off
+      :members:
+
+.. automodule:: adafruit_midi.note_on
+      :members:
+
+.. automodule:: adafruit_midi.pitch_bend_change
+      :members:
+
+.. automodule:: adafruit_midi.polyphonic_key_pressure
+      :members:
+
+.. automodule:: adafruit_midi.program_change
+      :members:
+
+.. automodule:: adafruit_midi.start
+      :members:
+
+.. automodule:: adafruit_midi.stop
+      :members:
+
+.. automodule:: adafruit_midi.system_exclusive
+      :members:
+
+.. automodule:: adafruit_midi.timing_clock
+      :members:
+