Starting from this release, Tengine is based on Nginx-1.0.12. Other changes
* Feature: adds the 'request_time_cache' directive, to get more precise
* Feature: adds the 'slice' module to get a part of a static file.
* Change: deletes unused browser detection.
* Bugfix: fixes a bug in upstream when reading header.
* Bugfix: fixes a bug in 'expires_by_types'.