add scaling documentation
Add http_hsts_enable (enabled by default with max-age=31536000) to Kore's configuration file.

If enabled Kore adds the HSTS header to every response.

- Additionally, fix some typos in the example configuration.
- Change default SSL cipher list again, no more RC4 and almost PFS for all browsers.
Do not kill a connection if nb->len is 0 when sending data.
Add http_keepalive_time configuration parameter.

Allows you to configure maximum amount of seconds an HTTP connection
can stay open (does not affect SPDY connections). If set to 0 it will
disable keep-alive all together.

Add some inttypes fluff.