http_renderer: various cleanups
http_renderer: file rename

--HG--
rename : plugins/http_renderer/src/httprnet.c => plugins/http_renderer/src/httprsrv.c
rename : plugins/http_renderer/src/httprnet.h => plugins/http_renderer/src/httprsrv.h
http_renderer: fixed a regression in httprprc.c
http_renderer: some more renaming