Ticket 329: Add IEEE compatibility library

The (scheme ieee) library exports the standard identifiers of IEEE 1178-1990. By my current reckoning, those identifiers are as follows:

- * / + < <= = > >= abs acos and angle append apply asin assoc assq assv atan begin boolean? call-with-current-continuation car case cdr ceiling char->integer char-alphabetic? char-ci<? char-ci<=? char-ci=? char-ci>? char-ci>=? char-downcase char-lower-case? char-numeric? char-upcase char-upper-case? char-whitespace? char? char<? char<=? char=? char>? char>=? close-input-port close-output-port complex? cond cons cos current-input-port current-output-port define denominator display do eof-object? eq? equal? eqv? even? exact->inexact exact? exp expt floor for-each gcd if imag-part inexact->exact inexact? input-port? integer->char integer? lambda lcm length let let* letrec list list-ref list? log magnitude make-polar make-rectangular make-string make-vector map max member memq memv min modulo negative? newline not null? number->string number? numerator odd? open-input-file open-output-file or output-port? pair? peek-char positive? procedure? quasiquote quote quotient rational? rationalize read read-char real-part real? remainder reverse round set-car! set-cdr! set! sin sqrt string string->number string->symbol string-append string-ci<? string-ci<=? string-ci=? string-ci>? string-ci>=? string-length string-ref string-set! string? string<? string<=? string=? string>? string>=? substring symbol->string symbol? tan truncate vector vector-length vector-ref vector-set! vector? write write-char zero?

As with any library other than (scheme base), implementations SHOULD (rather than MUST) provide this.