Fixed a bug in the schema for App and Content objects in avro protocol definition file

App and Content objects were missing fields, mislabeled and some fields
had wrong types. Fixed these bugs and carefully checked them against
OpenRTBAPI 2.1 specification. The Java files are regenerated by the
avro compiler which is part of the maven build using the
avro-maven-plugin.
UML Class diagrams for the BidRequest and BidResponse object heirarchies

Generated using ObjectAid Eclipse plugin. Both the image files (PNG) as
well as the plugin generated .ucls files are being committed.