[maven-release-plugin] copy for tag tchannel-0.4.0

[maven-release-plugin] copy for tag tchannel-0.3.6

[maven-release-plugin] copy for tag tchannel-0.3.5

[maven-release-plugin] copy for tag tchannel-0.3.4

[maven-release-plugin] copy for tag tchannel-0.3.3

[maven-release-plugin] copy for tag tchannel-0.3.2

[maven-release-plugin] copy for tag tchannel-0.3.1

uncaught exceptions should result in an UnexpectedError

stablized interface with doc & examples

bug fix for thrift/json response headers