为querySeter添加GroupBy方法

always use server's locale to parse date

When parsing the date without time, it's always using UTC date, which is
unexpected. If we want to use UTC date, it's recommend to set the
server's timezone as UTC, and keep the code flexible.

Update error.go

this caused `http: multiple response.WriteHeader calls` when using method `CustomAbort` or `Abort` when status is already in errMap like 404.

Added JWT plugin

Fix issue #1274: Add QuerySeter.Distinct()

httplib请求参数支持[]string

fix typo

fix example/chat i/o timeout

全局变量AutoRender为false时，run时不再编译模版；针对开发模式下，每个请求渲染模版时支持单独编译当前请求相关模版

fixed mux1 to mux

Added MapGet template func

Update router.go, add Flush for responseWriter

增加编译模版函数BuildTemplate可变参数，使之支持单个或多个模版的编译，同时针对开发模式，每个请求只编译当前请求相关模版，不再每次请求都编译全部模版

AutoRender为空，Controller.Render()不再执行，故无需编译模版

Fix #1269 extract godoc to own file.

typo fixed

registor==>register
innner ==> inner

Fix #1271 Add description from docs on beego.me to README
and also add same description to godoc