tar.1: convert to mandoc

- simplify usage line.
- add new flags (-m, -j and -z).
- fix typos.

tar.1

@@ -1,62 +1,60 @@
-.TH TAR 1 sbase\-VERSION
-.SH NAME
-tar \- create, list or extract a tape archive
-.SH SYNOPSIS
-.B tar
-.RB [ \-f
-.IR tarfile]
-.RB [ \-C
-.IR dir ]
-.RB [ - ] x | t
-
-.B tar
-.RB [ \-f
-.IR tarfile]
-.RB [ \-C
-.IR dir ]
-.RB [ - ] c
-.I dir
-
-.B tar
-.RB [ \-C
-.IR dir ]
-.B cf
-.I tarfile
-.I dir
-
-.B tar
-.RB [ \-C
-.IR dir ]
-.B x|tf
-.I tarfile
-
-.SH DESCRIPTION
-.B tar
+.Dd January 31, 2015
+.Dt TAR 1 sbase\-VERSION
+.Os
+.Sh NAME
+.Nm tar
+.Nd create, list or extract a tape archive
+.Sh SYNOPSIS
+.Nm
+.Op Fl C Ar dir
+.Op Fl jz
+.Fl x Op Fl m
+|
+.Fl t
+.Op Fl f Ar tarfile
+.Nm
+.Op Fl C Ar dir
+.Op Fl jz
+.Fl c Ar dir
+.Op Fl f Ar tarfile
+.Nm
+.Op Fl C Ar dir
+.Op Fl jz
+.Fl cf
+.Ar tarfile Ar dir
+.Sh DESCRIPTION
+.Nm
 is the standard file archiver. Generally the archives
 created with it are further compressed.
-.SH OPTIONS
-.TP
-.B x
-extract tarball from stdin
-.TP
-.B t
-list all files in tarball from stdin
-.TP
-.BI c\  path
-creates tarball from
-.I path
-and prints it to stdout
-.TP
-.BI f\  tarfile
-Make
-.I tarfile
-be the archive, rather than stdin or stdout.
-.TP
-.BI C\ dir
-Change dierctory to
-.I dir
+.Sh OPTIONS
+.Bl -tag -width Ds
+.It Fl c Ar path
+Creates tarball from
+.Ar path .
+.It Fl C Ar dir
+Change directory to
+.Ar dir
 before beginning.
-.SH SEE ALSO
-.IR ar (1)
-.IR gzip (1)
-.IR bzip2 (1)
+.It Fl f Ar tarfile
+Make
+.Ar tarfile
+be the archive, rather than stdin or stdout.
+.It Fl j
+Compress archive using bzip2. The
+.Xr bzip2 1
+utility must be installed separately.
+.It Fl m
+Do not preserve modification time.
+.It Fl t
+List all files in tarball.
+.It Fl x
+Extract tarball.
+.It Fl z
+Compress archive using gzip. The
+.Xr gzip 1
+utility must be installed separately.
+.El
+.Sh SEE ALSO
+.Xr ar 1 ,
+.Xr bzip2 1 ,
+.Xr gzip 1