* optimized functions for inlining
* added note regarding ResponseWriterWrapper
* optimzed browseWrite* methods for FileServer
* created benchmarks for comparison
* creating browseListing instance in each function
* created benchmarks for openResponseWriter
* removed benchmarks of old implementations
* implemented sync.Pool for byte buffers
* using global sync.Pool for writing JSON/HTML
- Fix static responder so it doesn't replace its own headers config,
and instead replaces the actual response header values
- caddyhttp.ResponseRecorder type optionally buffers response
- Add interface guards to ensure regexp matchers get provisioned
- Use default HTTP port if one is not explicitly set
- Encode middleware writes status code 200 if not written upstream
- Templates and markdown only try to execute on text responses
- Static file server sets Content-Type based on file extension only
(this whole thing -- MIME sniffing, etc -- needs more configurability)