Renaming an argument should also rename its usage in the keyword

[tarand]

Assume you have a keyword in a robot-test files that defines an argument ${arg}. Typically, this argument is used (at least) once in the code of the keyword. Now if you rename the argument via robotide (e.g. to ${argument}), its usage is NOT renamed at the same time, which produces a syntax error. It would be desirable that all usages of this argument are also updated.