text: Title: Collections: `Get From Dictionary` should accept a default value
  Body: [Pop From Dictionary](https://robotframework.org/robotframework/latest/libraries/Collections.html#Pop%20From%20Dictionary) has support for returning a default value if the key isn't found in the dictionary. e.g.
  ```robot
  Pop From Dictionary  ${myDict}  myKey  myDefaultValue
  ````
  
  I think it'd be great if `Get From Dictionary` also support having a default value passed to it. 🙂
  
  e.g.
  ```robot
  Get From Dictionary  ${myDict}  myKey  myDefaultValue
  ```
  