Create File formats structures to use in nstool or wherever

[sagumamugas]

I tried to create a GUI to preview the files nstool can read, but many of the process is done in nstool.
Maybe can be a good point move many of the process to libpietendo to allow to use in other projects.
The idea is create fileformat structures in libpietendo that read the structure of the files and then the program that use libpietendo use that structures.

Here can see the idea for the fileformat structures and here the use in nstools

[jakcron]

That's a good point, a lot of the processing logic is done in NSTool. At some point I may move more of the logic to libpietendo, so that other programs can use the logic.