fix timeout 0

timeout 0 would NOT timeout, but nothing happened
url-encode tmpl allow inputting encoded contents
reset TcpConn by hijack
profile command support tcp-write

tcp-write directly write response content in tcp but http
ungzip content when caching gzip content
update index and usage introduction
Version 0.2.3

+ support tcp override http
* fix bug of version code
* fix bug of caching gzip content without ungzip
* fix bug of timeout 0
* update index and usage introduction