lots of fixes and improvements
limitations: see comments at top of mod_deflate.c
missing functionality: encode streaming response
(module currently requires response be collected before being sent)
potential functionality: addition of compressed file cache would
allow mod_deflate to fully supplant mod_compress in lighttpd 1.4.x
"Adding mod_deflate to 1.4.xx"
"mod_deflate backport compile error if ENABLE_MMAP not defined"
github: closes #67