Support context(cancel)
Fix concurrency issue.
More request method support.
Json request support.
Add OPT_DEBUG
option.
Remove constructor params, add Defaults
method to set default options.
Make default client as primary to keep things simple.
Add default client for convience.
Fix gzip.
Improve constructor: support both default options and headers.
Pass through useragent during redirects.
Support error checking.
Fix cookie, add cookie retrieving methods
Add shortcut for response
API improvements
Cookie support
Concurrent safe
Make http.Client
reusable
Rewrite API, make it simple
Initial release