Added functionality to get store schema

Example:
==========

 curl http://localhost:8080/schemata/dGVzdA==
{"key-serializer": "SerializerDefinition(name = string, schema-info =
{}, compression = null)", "value-serializer": "SerializerDefinition(name
= string, schema-info = {}, compression = null)"}
Cleaned up code based on Vinoth's review
Adding sample configs for Voldemort Coordinator
Implement metadata bootstrapping for Java Rest Client
Bug fix in RESTErrorHandler - adding the right content length in the response header
Update CONTRIBUTORS

Long missing update for the current Voldemort Team at Linkedin
Fixed case with statsTrackingStore not being wrapped around properly
with DynamicTimeoutStoreClient since ser. and compression were disabled
For some reason the method that I had added to retrieve storedefs was
missing adding it back
 Some cleanup
Added comments
Add more locations to gitignore