Update VERSION to 3.0.0

[s-martin]

Idea:

• finally decide on name for library
• move copyright and license info to ORIGINAL_GALIB_COPYRIGHT.txt and ORIGINAL_GALIB_LICENSE.txt (which uses some sort of BSD license)
• decide on license for forked Modern GAlib and add license
• in source code keep original copyright&license comment on unchanged files, add in addition copyright&license comment from Modern GAlib to existing comment, use only copyright&license comment from Modern GAlib for completely new files.
• use version 1.0 for Modern GAlib
• decide, if GNU examples should be removed.