Fixes #206

Making HttpServerRequest.getContent() and HttpClientResponse.getContent() lazily subscribable.
Merge branch 'master' of https://github.com/Netflix/RxNetty
Added missing copyrights
Making HttpClient.submit() returning only a single item (as expected)

Also disabling mavenLocal() from the build. This causes cloudbees builds to fail if the local repo gets corrupted.
Removing pre-created exception instances from UnicastContentSubject.
Merge pull request #207 from NiteshKant/master

Fixes #206
Fixes #199

Wrong metric event was being used.
Updated CHANGES.md for release 0.3.12
Merge pull request #212 from NiteshKant/master

Fixes #199
Fixes #216 (Remove use of Subject in HttpClientResponse and HttpServerRequest)
Create .travis.yml
Merge branch '0.x' of https://github.com/Netflix/RxNetty into 0.x
Merge pull request #221 from NiteshKant/0.x

Fixes #216 (Remove use of Subject in HttpClientResponse and HttpServerRequest constructors)
Fixes #223 (Client connections receiving SSE responses should never be pooled & reused)

Channel attribute "rxnetty_http_discard_connection" is used by `ObservableConnection` to discard a connection on close. SSE Inbound handler sets this attribute as a connection on which SSE response has started should never be pooled.
Fixes #226 #225

 Issue 226: Flushing response when `RequestHandler` emits an error or throws an unexpected error.
 Issue 225: Connection close for HttpClient.submit() is now done when the content is completed or the (only) subscriber to the content subject unsubscribes.
Invoking onUnsubscribeAction for dispose also.

If no one subscribes to the UnicastContentSubject, for HttpClientResponse, the connection would never be closed.

For this reason we should also call the onUnubscribe action when the content is disposed.
Fixes #214 #228

Issue #214 Provde getChannel() method in HttpServerRequest
Issue #228 Provide getChannel() method in DefaultChannelWriter and deprecate getChannelHandlerContext()
Fixes #230 (FlatResponseOperator does not emit any item if there is no content.)

Also, fixed the test failure for previous PR
Merge pull request #227 from NiteshKant/0.x

Fixes #223 #225 #226 #214 #228 #230
Updates to CHANGES.md for 0.3.13