Make it possible to read text columns in fast_fancy_read

git-svn-id: svn+ssh://rubyforge.org/var/svn/tioga/trunk/tioga@640 f6f669a6-2b79-499e-8f05-be2b991fc3d0
Fix memory (re)allocation problems in the new fast_fancy_read code

git-svn-id: svn+ssh://rubyforge.org/var/svn/tioga/trunk/tioga@641 f6f669a6-2b79-499e-8f05-be2b991fc3d0