Major refactoring done. Loading .fzm files functionnality lost.
BugFix: the comparison between versions was wrong. 

It was causing a bug in the loading of files. Indeed, there are some
code used for backward compatibility but the versions numbers were
turned into String for comparison. This was creating the bug.

Now the versions are correctly compared.
Replaced the ugly attributes lists with an object.

Several @Deprecated functions have been added for parts of the code that
were iterating over the attribute list.

I will still need an other refactoring iteration.
Homogenize the copyright notices.