first round of protocol parsers optimizations

preliminary api for language-independent body read

another step

completed body read language independent implementation

ported gevent to the new read/write api

ported websockets to the new read/write api

removed channels subsystem

removed channels subsystem

ported lua to the new read/write api

fixed post-buffering

readline is still broken

improved request body readline

very difficult test for readline()/read() combo passed

other improvements in postbuffering/read/readline

ported --http-socket to the new api

added X-Forwarded-SSL management

removed old api

more refactoring

ported the RACK plugin to the new api

ported psgi plugin to the new api

defintely removed clustering

simpified ifdel hell

simpified ifdef hell

removed useless configuration options