Move generated functions

[Adeel Asghar]

At the moment, we generate code like:

void functionDAE(...) {
  ...;
}

And call it from the runtime:

functionDAE(...);

This is a problem for FMUs since there are now two functions available with the name functionDAE. In order to make the runtime work properly, we need to move this code into a struct and from the run-time call {{{#!c
data->functionDAE(...);
}}}

The actual definitions of functions like functionDAE needs to use something similar to the fmiFullName() macro. Or other approach that accomplishes the same effect.