Media support (such as Path) in Níma HTTP1 buffer into memory

[Verdent]

Media support in Níma HTTP1 currently does not work properly.
HttpCallEntityChain buffers everything into the memory, instead of writing into the request OS. It should rather use something similar to ClientConnectionOutputStream which performs sent entity analysis to determine proper transfer-encoding and content-length.

Once this is changed, it will break our current redirect support for entities introduced in #6804. Once the following issue is fixed #6992, it should introduce fix usable also by this issue.

Tomas Langer:
For example when you call ServerResponse.send(Paths.get("/my/file.txt")) the file will be fully buffered into memory.

Possible solutions (there may be more):

• have a boolean streaming() on media supports to tell the server and client that this really must be streamed and not cached in memory
• have some advanced logic to buffer a certain (max) amount in memory for any provider, and if more bytes would be written, start sending them over the network

In both cases we need to refactor the method send(Object) on server response (and appropriate one on client request)