setting default value to message_ttl as 30 minutes to avoid memory leak when stored is on and message_ttl was not configured

change use of ngx_http_finalize_request on ngx_http_push_stream_send_response_finalize function to run cleanup connection properly

adding a way to pass extra parameters in subscriber url, the extraParams function will be called before each connection to server

Added a End of batch flag for client of pushtream.js to know when it is finished receiving a long polling batch. End of batch flag is set to true for all transport except long polling  when the client can receive a batch of messages at once in between 2 long polling request. This is to help client pushstream.js to implement some filter logic at batch level (for example discard stale messages)

 enable push stream client to use 443 as non ssl port to prevent caching that occurs on some proxies on 80 port

fix initial temp pool size to be 1024 multiple, the old value cause error when try to allocate more memory than the initial value

optimizing message creation and check return of function ngx_http_push_stream_apply_text_template calls for errors

fix memory leaks when saving channels on a rbtree with ids which collides, problem inherited from Nginx and reported by Lanshun Zhou

removing conditional use of ngx_time_update function, versions 0.7.x are no longer supported, since version 0.2.5