fix mandoc warnings

- sort references in SEE ALSO section to section number, name.
- cols.1: proper order of sections.
- wrap lines to max 79 column length.

wc.1

@@ -10,9 +10,13 @@
 .Op Ar file ...
 .Sh DESCRIPTION
 .Nm
-.Pp
-prints the number of lines, words, and bytes in each file.  If any flags are
-given, wc will print only the requested information.  If no files are given, wc
+prints the number of lines, words, and bytes in each file. If any flags are
+given,
+.Nm
+will print only the requested information. If no
+.Ar files
+are given,
+.Nm
 reads stdin.
 .Sh OPTIONS
 .Bl -tag -width Ds