Audit cols(1)

1) Refactor manpage.
2) De-globalize local values.
3) update usage().
4) sort local variable declarations.
5) fix wrong argument in strtonum (3 -> 1).
6) argc-argv style, boolean style.
7) check bytes > 0 before accessing b.lines[i][bytes - 1]
   relying on len only makes sense but let's not push it.
7) don't break on maxlen > (chars - 1) / 2. This didn't even
   make sense.
8) _correctly_ calculate cols and rows in a readable way.
9) Rewrite loop over rows and cols in a readable way and
   using putchar in a loop instead of printf-magic or fputs
   where not necessary.

cols.1

@@ -1,4 +1,4 @@
-.Dd February 19, 2015
+.Dd March 8, 2015
 .Dt COLS 1
 .Os sbase
 .Sh NAME
@@ -15,7 +15,8 @@ reads each
 in sequence and writes them to stdout, in as many vertical
 columns as will fit in
 .Ar num
-character columns. If no
+character columns.
+If no
 .Ar file
 is given,
 .Nm
@@ -27,17 +28,15 @@ tries to figure out the width of the output
 device. If that fails, it defaults to 65 chars.
 .Sh OPTIONS
 .Bl -tag -width Ds
-.It Fl c Ar chars
-Set the maximum number of character columns to use
-(unless the input contains lines longer than
-.Ar num
-characters).
+.It Fl c Ar num
+Set maximum number of character columns to
+.Ar num ,
+unless input lines exceed this limit.
 .El
 .Sh ENVIRONMENT
-.Bl -tag -width COLUMNS
+.Bl -tag -width Ds
 .It COLUMNS
-If this variable is set, the value is used as the
-width of the output device.
+The width of the output device.
 .El
 .Sh HISTORY
 .Nm