validity check for "mpfr1" must be more sophisticated for 64 bit


git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rmpfr@197 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
new mpfrImport(); works (partly at least).

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rmpfr@198 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
import more from gmp

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rmpfr@199 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
add a line  " .. some differences .. expected .."


git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rmpfr@200 edb9625f-4e0d-4859-8d74-9fd3b1da38cb