Adding pt doc "Testing Components and Controllers"

I tried to write this doc about "Testing Components and Controllers".
The text I based on discussions on the mailing list and docs from VRaptor3.

Just in portuguese, so when you accept the doc, I can try translate to English.  :smiley: 

Sorry for some possible errors.
Maybe: "Para testar esse controller, podemos usar o `MockResult` e `MockValidator` como dependência:"