license change:

LGPLv3+ for code
FDLv1.3+ for mpc.texi
simple disclaimer for supporting files (README, NEWS, INSTALL)
tests/memory.c: replaced by version from mpfr-3.0.1
mpfr.texi: small cleanups; added real authors again, while keeping copyright
   notice with INRIA


git-svn-id: svn+ssh://scm.gforge.inria.fr/svnroot/mpc/trunk@1027 211d60ee-9f03-0410-a15a-8952a2c7a4e4