sh: Remove unused man page for echo builtin.

The information in sh(1) about the echo builtin is equivalent, though less
extensive.

The echo(1) man page (bin/echo/echo.1) is different.

Unfortunately, sh's echo builtin and /bin/echo have gone out of sync and
this probably cannot be fixed any more.

Reported by:	uqs (list of untouched files)
MFC after:	1 week

bin/sh/bltin/echo.1

@@ -1,114 +0,0 @@
-.\"-
-.\" Copyright (c) 1991, 1993
-.\"	The Regents of the University of California.  All rights reserved.
-.\"
-.\" This code is derived from software contributed to Berkeley by
-.\" Kenneth Almquist.
-.\" Copyright 1989 by Kenneth Almquist
-.\"
-.\" Redistribution and use in source and binary forms, with or without
-.\" modification, are permitted provided that the following conditions
-.\" are met:
-.\" 1. Redistributions of source code must retain the above copyright
-.\"    notice, this list of conditions and the following disclaimer.
-.\" 2. Redistributions in binary form must reproduce the above copyright
-.\"    notice, this list of conditions and the following disclaimer in the
-.\"    documentation and/or other materials provided with the distribution.
-.\" 4. Neither the name of the University nor the names of its contributors
-.\"    may be used to endorse or promote products derived from this software
-.\"    without specific prior written permission.
-.\"
-.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-.\" SUCH DAMAGE.
-.\"
-.\"	@(#)echo.1	8.2 (Berkeley) 5/4/95
-.\" $FreeBSD$
-.\"
-.Dd May 4, 1995
-.Dt ECHO 1
-.Os
-.Sh NAME
-.Nm echo
-.Nd produce message in a shell script
-.Sh SYNOPSIS
-.Nm
-.Op Fl n | Fl e
-.Ar args...
-.Sh DESCRIPTION
-The
-.Nm
-utility prints its arguments on the standard output, separated by spaces.
-Unless the
-.Fl n
-option is present, a newline is output following the arguments.
-The
-.Fl e
-option causes
-.Nm
-to treat the escape sequences specially, as described in the following
-paragraph.
-The
-.Fl e
-option is the default, and is provided solely for compatibility with
-other systems.
-Only one of the options
-.Fl n
-and
-.Fl e
-may be given.
-.Pp
-If any of the following sequences of characters is encountered during
-output, the sequence is not output.
-Instead, the specified action is
-performed:
-.Bl -tag -width indent
-.It Li \eb
-A backspace character is output.
-.It Li \ec
-Subsequent output is suppressed.
-This is normally used at the end of the
-last argument to suppress the trailing newline that
-.Nm
-would otherwise output.
-.It Li \ef
-Output a form feed.
-.It Li \en
-Output a newline character.
-.It Li \er
-Output a carriage return.
-.It Li \et
-Output a (horizontal) tab character.
-.It Li \ev
-Output a vertical tab.
-.It Li \e0 Ns Ar digits
-Output the character whose value is given by zero to three digits.
-If there are zero digits, a
-.Dv NUL
-character is output.
-.It Li \e\e
-Output a backslash.
-.El
-.Sh HINTS
-Remember that backslash is special to the shell and needs to be escaped.
-To output a message to standard error, say
-.Pp
-.D1 echo message >&2
-.Sh BUGS
-The octal character escape mechanism
-.Pq Li \e0 Ns Ar digits
-differs from the
-C language mechanism.
-.Pp
-There is no way to force
-.Nm
-to treat its arguments literally, rather than interpreting them as
-options and escape sequences.