Add support for configuring the HttpRequestDecoder when creating an HttpServer

[wilkinsona]

A Spring Boot user has raised an issue that's caused by Netty's default configuration that limits the initial line of an HTTP request to 4096 bytes. As far as I can tell, Reactor Netty doesn't allow this to be configured as the default HttpRequestDecoder constructor is used.

Would it be possible to expose the configuration options offered by HttpRequestDecoder to users?

[balopat]

+1

[violetagg]

Covered by #256