[ptx] merging more than one .pto file

[Pablo d'Angelo]

Hi Ed,

>   hugin: PanoramaMemento.cpp:530: bool
>          PT::PanoramaMemento::loadPTScript(std::istream&,
>          const std::string&): Assertion `nr < optvec.size()'
>          failed.
> 
> I can see that it is trying to parse a 'v' line, but I'm not sure why
> the variable number would exceed the "optvec" size, or what the optvec
> is actually accumulating.
> 
> It wasn't immediately clear what I was doing wrong.  In case the order
> was important, I tried moving all 'i' lines above everything else, but
> that wasn't the problem.

Actually, the order is imporant. while I haven't tried moving all v
lines to the end, they have to be after all  i lines.

you could just delete all v lines as well, since they just
contain the ticks on the optimize panel. Tried that and it worked.

ciao
  Pablo