RFI 0001: regarding the "flag" returned
by READ-LINE at end of file.
RFI 0002: search orders in which a given wordlist occurs more than once.
RFI 0003: What's allowed between CREATE and DOES>
RFI 0004: standard punctuation for double-cell numbers.
RFI 0005: initiation semantics.
RFI 0006: Writing to Input Buffers.
RFI 0007: distinction between "immediacy" and "special compilation semantics"