- most of pippy is GPLv2+, but library/pippy/physics is GPLv3+,
  conflict unresolved,

- add missing activity license file COPYING chosen based on
  activity.info license field GPLv2+,

- add missing copyright headers to source files that either didn't
  have them (library/pippy/{__init__,sound}.py) or had abbreviated
  versions (library/pippy/{console,game}.py)

- spell organisation name correctly (s/Per/per),

- express copyright years in full,

- include GPLv3+ LICENSE from Elements upstream SVN, as
  library/pippy/physics/LICENSE

Fixes sugarlabs.org #1571 and laptop.org #9181.