Because of confusion when indentation level is raised and thus tabs or
spaces should be used when aligning code, this commit switches to tabs
to avoid any further confusion.
The saved game files now start with a header and version which allows
to do some sanity check and will allow to change the format in the
future if needed.
Also the MetaEngine can now be queried for the meta infos of a save
state.
There has been many other changes like copy/pasting room definitions,
skeleton for image decoder, ..
Getting supernova mod format support seems to be a good next step.
