http-client-branch: more no body tests

http-client-branch: review comment onSubscribe before onXXX

http-client-branch: review comment add more checks to tests for redirect

http-client-branch: review comment Add toString to HttpHeaders

http-client-branch: (WebSocket) Demand in Receiver

http-client-branch: fixing synchronization problem in ping test

http-client-branch: review comment add missing license header

http-client-branch: review comments BodySubscriber should specify how an implementation is expected to behave.

http-client-branch: added ping support to test http2 server and some test pings from server to client in the BasicTest

http-client-branch: (WebSocket) cleanup & simplifications

http-client-branch: relax server side exception handling in CancelledResponse test

http-client-branch: review comment remove trailing white space

http-client-branch: fix cancel() to close the HTTP/1 forcefully as it cannot be reused

http-client-branch: (WebSocket) cleanup

http-client-branch: (WebSocket) testing sending messages

http-client-branch: further review comments on error handling in BufferedSubscriber

http-client-branch: review comments add missing links to pre-defined BodyHandlers

http-client-branch: review comment on buffering subscriber, and new test to verify the change

http-client-branch: review comment BodySubscriber::asInputStream

http-client-branch: review comments add buffering cancallation test

http-client-branch: review comments remove superflous ssl permission check

http-client-branch: review comments minor spec cleanup

http-client-branch: (HPACK) renamed test

http-client-branch: (WebSocket) moving http proxy-related code to OpeningHandshake

http-client-branch: HttpRequest/HttpResponse api change: remove link between requests, add links between responses. Fixed some redirection problems

http-client-branch: review comments, minor WS spec updates

http-client-branch: (WebSocket) CompletableFuture -> MinimalFuture

http-client-branch: review comments on WS spec

http-client-branch: remove usage of deprecated Class::newInstance

http-client-branch: removed RS TCK-incompatible publisher, updated subscribers so they'd pass TCK

http-client-branch: avoid picking buffer size resulting in too long delays for BufferingSubscriberTest.java

http-client-branch: merge

http-client-branch: merge with default

http-client-branch: (WebSocket) cleanup. Removed not needed classes. I'll bring some of them in later, when I need them.

http-client-branch: (WebSocket) API update

http-client-branch: remove some degenerate test cases from BufferingSubscriberTest

http-client-branch: more debugging, and hopefully a fix, for a FlowTest intermittent failure (ERROR AT END)

http-client-branch: minor doc formatting

http-client-branch: (WebSocket) builder change

http-client-branch: review comment asFileImpl sneaked into the API

http-client-branch: more precision for GET() in HttpRequest.Builder

http-client-branch: more precision for headers in HttpRequest.Builder

http-client-branch: minor doc formatting in HttpRequest

http-client-branch: moved noBody() to HttpRequest.BodyPublisher

http-client-branch: better diagnosis of expected exceptions

http-client-branch: minor doc tweaks in HttpRequest

http-client-branch: typo in HttpClient.java

http-client-branch: minor doc tweak in HttpClient.java