fixing open-string-output-port (R6RS)
making io.tostring! more consistent
adding newlines to boot file; wastes space but will allow more
efficient diffing
making io.write output chars as utf8;
suddenly switching to UTF32 was not intuitive
adding stream argument to newline (R6RS)
adding several more scheme compatibility procedures
do not need to be written in terms of the base language any more
moving handling of internal define and multiple-body-lambda to the
compiler where it belongs. macroexpand now only handles syntax.