title: Change the parameters in text with fields
body: <p>I want to change these items in my context with dynamic fields. 
  parameters: "Dear {prefix} {name} {family}, thank you for accepting....".
  I mean when a user write {family} in his text box, the program must detect it as a key word and replace it with a dynamic fields. In summery i want to edit a text with dynamic fields by user form his panel.
  can any body help me?</p>