…header that determines whether or not to replace underscores with hyphens.

Previously, underscores were replaced unconditionally.
Currently each of the functions has another boolean argument. If it's false, underscores would not be touched. If it's true, they would.
The default value of the argument is true.

…ptions), in which the only possible option currently is replace_underscores.

…keepalive option for the request.

 - Now receive and send operations can be done simultaneous from several threads.
 - A different timeout can be set for receive and send.
 - Added fake_close for the client socket (ngx.req.socket), so that a thread that receives on this socket can be notified that we don't want to read from it anymore.

…s to receive just like BSD's recv call, meaning the maximum number of bytes given.

This will only work only when a number is given as the first parameter for receive.
Note that this differs from the original LuaSocket API.

… the "Location" response header, Nginx won't try to make absolute in case it's relative.

Default is on.

…response headers weren't set, ngx_lua won't enforce setting the content type header.

Default is on, and this causes the default behavior - if the headers aren't set, then the 'Content-Type' header is set to the default content type.

 ngx.thread.kill - kills a thread.
 ngx.thread.kill_sleeping - either kills immediately a sleeping thread, or, if the thread is not sleeping, can wait for it to end. Useful for a thread that has a loop in which it sleeps.

…eter as a string.

If the method string isn't a known Nginx method, it is still passed (and Nginx considers it as unknown).

…to be performed in a streaming fashion.

Conflicts:
	src/ngx_http_lua_common.h
	src/ngx_http_lua_module.c

Conflicts:
	src/ngx_http_lua_common.h
	src/ngx_http_lua_module.c

…ts when using ngx.thread.kill_sleeping.

Now removing the timer.

…(even when enforce_content_type is off).

…request body before using it.

This makes it possible to implement 'streaming' protocols, in which both client and server can read and write at the same time (such as forward HTTPS proxy with the CONNECT method).