[IMPROVEMENTS]
- Added MIME type for apk files #514 (allanwhiteford)
- Allow passing custom formatters to Plack::Middleware::AccessLog #515 (frew)
- Allow '0' be a valid category for log4perl middleware #523
- Doc fix for Plack::Runner #528 (polettix)
- Doc improvements for -R/-M command line #529 (mickeyn)
- Bind test server explicitly on 127.0.0.1, not 0.0.0.0
- Support single-process manager in FCGI #535 (ianburrell)
- Optimize Plack::Response header builder #540 (kazeburo)