Add support for asynchronous REST calls

Async web services are getting more popular. Currently, rest-assured does not 
support these calls. Servlet 3 enabled these async behavior, MBaaS (StackMob, 
Parse, etc.) have purely async services, and others are adopting this pattern.

JAX-RS 2.0 has a web service client class (javax.ws.rs.client.Client) that can 
wait for an async web service call to complete before proceeding (see async() 
method). Having a similar behavior/ability to wait for an async call to 
finish/return would be very useful.

Forum topic (and example code of Client's async usage) here: 
https://groups.google.com/forum/#!topic/rest-assured/aWWWehfUrV0

Original issue reported on code.google.com by c.yem...@gmail.com on 7 Feb 2014 at 3:24

suvallur / rest-assured

Add support for asynchronous REST calls #307