Re-layout project to match Arduino Library reqs

CHANGES.txt

@@ -1,3 +1,5 @@
+2.2
+   * Change code layout to match Arduino Library reqs
 2.1
    * Add MAX_TRANSFER_SIZE def to chunk messages if needed
    * Reject topic/payloads that exceed MQTT_MAX_PACKET_SIZE

library.properties

@@ -1,5 +1,5 @@
 name=PubSubClient
-version=2.1
+version=2.2
 author=Nick O'Leary <nick.oleary@gmail.com>
 maintainer=Nick O'Leary <nick.oleary@gmail.com>
 sentence=A client library for MQTT messaging.