fix fname,by extension to identify the file type on mac and windows.

Fix #1237

Update validators.go

Support virtual operators paragraph 170！

Package description uses same text as the README.

fix FilterHandler crash issue 

Filter Handler will crash with error assignment to entry in nil map , params from function Tree.Match() maybe nil.

pull from stable

Revert "Revert "fix multiple filters execute issue""

Revert "fix multiple filters execute issue"

fix multiple filters execute issue

ex:
	beego.InsertFilter("/*", beego.BeforeExec, FilterLoginCheck1,false)
	beego.InsertFilter("/*", beego.BeforeExec, FilterLoginCheck2)

In function  FilterLoginCheck1 , I'll write data via ResponseWriter, and w.started = true
FilterLoginCheck2 won't be executed, it should be.

Develop

support eq&ne for orm

Don't overwrite the params from function  ValidRouter

just add new params to context.Input.Params

Let filter function get more params info from ctx.Input.Params

remove space after int()& add sort for commentsRouter file

Add GetMulti method for Cache interface