add avro schema to support other languages

Add [Apache Avro](http://avro.apache.org/) protocol schema for other [Supported Languages](https://cwiki.apache.org/confluence/display/AVRO/Supported+Languages).It was only a partial modification to the attempt. Not centain if such avro schema can fit this project.

```
$ nosetests test/test_avroproto.py
....
----------------------------------------------------------------------
Ran 4 tests in 0.002s

OK
```
If I am not mistaken, `version_info` is the version of Python installed. The script says `simplejson` is required in Python versions 2.5 and earlier. This is so old, even [Debian squeeze](https://packages.debian.org/squeeze/python) is using Python 2.6.

Please remove `simplejson` from the requirements.