add push_stream_header_template_file directive to be possible store the header template in a different file

Signed-off-by: Wandenberg <wandenberg@gmail.com>

publish the message to all connected channels in javascript sendMessage function like when using websocket connection

fix #161 which reported a DoS on message formatter when text contains huge number of template patterns
Signed-off-by: Wandenberg <wandenberg@gmail.com>

clarify basic configuration example and nginx versions compatibility to close #145 and fix clone url to close #135

Co-Authored by: Roman Kuzmin <romanoza@gmail.com>
Signed-off-by: Wandenberg <wandenberg@gmail.com>

ensure all queue members are initialized to not produce errors on calling remove function, without insert them on a queue

remove global references to main module conf, ping and long polling timeout messages, and shared memory zones

add push_stream_timeout_with_body directive to indicate whether send a full message on timed out long polling connections, or not