Make nginx support file-aio and pcre-jit

--with-file-aio allows you to specify 'aio' which can be desirable
http://nginx.org/en/docs/http/ngx_http_core_module.html#aio

--with-pcre-jit is disabled by default, requires jit support in libpcre
Makes processing regexes (i.e. rewrites) faster
http://nginx.org/en/docs/ngx_core_module.html#pcre_jit
Bump pcre version to 8.34 (latest)

Tested rebuilds of nginx, nmap and php... all were fine
Build pkg/pcre respecting butch-optflags
Build pcre with --enable-jit

Requisite for nginx to use pcre jit feature

Potentially this could cause issues on some grsec systems but
so far so good in my own testing