doco srfi-1 count

[Kevin Ryde]

I noticed "count" from srfi-1 doesn't appear in the manual.  Assuming
that's only an accidental ommision I thought to propose the addition
below.

        * srfi-modules.texi (SRFI-1 Length Append etc): Add count.

What's described is per the srfi-1 spec, but the words are by me.  For
ease of reading the text is:

 - Scheme Procedure: count pred lst1 ... lstN
     Return a count of the number of times PRED returns true when
     called on elements from the given lists.

     PRED is called with N parameters `(PRED ELEM1 ... ELEMN)', each
     element being from the corresponding LST1 ... LSTN.  The first
     call is with the first element of each list, the second with the
     second element from each, and so on.

     Counting stops when the end of the shortest list is reached.  At
     least one list must be non-circular.

srfi-modules.texi.count.diff
Description: Text document