added FILE_IO workspace containing wrappers for FILE I/O functions

git-svn-id: http://svn.savannah.gnu.org/svn/apl/trunk@402 bd74f7bd-1a55-4bac-9fab-68015b139e80
apl.texi update

git-svn-id: http://svn.savannah.gnu.org/svn/apl/trunk@403 bd74f7bd-1a55-4bac-9fab-68015b139e80