The programs collected in /acme/edit offer a sam-like command interface
to acme windows.  The guide file
	/acme/edit/guide
holds templates for several editing operations implemented
by external programs.  These programs, composed in
a pipeline, refine the sections of a file to be modified.
Thus in sam when one says
	x/.*\n/ g/foo/ p
in /acme/edit one runs
	x '/.*\n/' | g '/foo/' | p
The e command, unrelated to e in sam, disambiguates file names, collects
lists of names, etc., and produces input suitable for the other tools.
For example:
	e '/usr/rob/acme:0,$' | x /oldname/ | c /newname/
changes oldname to newname in all the files loaded in acme whose names match
the literal text /usr/rob/acme.

The commands in /acme/edit are
	e
	x
	g
	c
	d
	p
	pipe	(like sam's | , which can't be used for syntactic reasons)

p takes a -n flag analogous to grep's -n.  There is no s command.
e has a -l flag to produce line numbers instead of the default character numbers.
Its implementation is poor but sufficient for the mundane job of recreating
the occasional line number for tools like acid; its use with the other commands
in this directory is discouraged.
