* Fix pf_server_new: pass own copy of proxyConfig
The lifecycle of proxyConfig passed to pf_server_new is unknown,
so pass proxyServer->config copy to modules.
* Early free parsed proxyConfig
* Split out proxy headers and moved to public API to allow external
modules to be built.
* Split proxy into proxy library and proxy binary. The library
can be used by other applications and provides a simple API
* Improved channel passthrough, now all channels including dynamic
channels work.
* Extended module API to hook more events, improved module samples
* Cleaned up proxy code, removed global static variables used,
added WINPR_ASSERT
