- added a GPL copyright notice
- modified the default class invariant from doubleeta to j, to make
  sure that a working class invariant is chosen by default
- suppressed printing of j-invariants and curve equations leading to
  wrong cardinalities
- added texinfo documentation


git-svn-id: svn+ssh://scm.gforge.inria.fr/svnroot/cme/trunk@38 2f087028-0334-4b02-9214-82c62fe11c84