first pass for new error handling infrastructure
Merge pull request #420 from danhyun/master

Issue #413 - Improve Error Handling Infrastructure
Convert TestHttpClient to be based on the ratpack httpclient

Add autoclosable to the TestHttpClient, DefaultTestHttpClient, and BlockingHttpClient

Change TestHttpClient to be based around actions configuring the request.
Set timeout on blocking httpclient latch so bad request specs don't hang the testing.
Most of the core tests passing
Update ResponseSpec
working on multi part
Added cookie support to the DefaultTestHttpClient

Updated the formhandling spec with multipart form support
Set ContentLength in BlockingHttpClient
Coding Convention Rules