* doc/am-utils.texi (opts Option): document new pcfs options

* doc/am-utils.texi (opts Option): document new pcfs options
longname, nowin95, shortname, uid=N, gid=N, mask=N, and dirmask=N.

* amd/ops_pcfs.c (mount_pcfs): process new pcfs options longname,
nowin95, shortname, uid=N, gid=N, mask=N, and dirmask=N.

* include/am_compat.h: provide compatibility mnttab string names,
if needed, for pcfs mount options longname, nowin95, shortname,
uid=N, gid=N, mask=N, and dirmask=N.

* include/am_utils.h: extern for hasmntstr().

* libamu/mtab.c (hasmntstr): new function to return the string
value following a mount option, up to the next comma-delimited
options.

* configure.in: check for mnttab and pcfs options longname,
nowin95, and shortname.

* Makefile.am (EXTRA_DIST_M4): distribute new macro
check_mnt2_pcfs_opt.m4.

* m4/macros/check_mnt2_pcfs_opt.m4: new macro to check for pcfs
mnttab and mount options.