bug#10881: 24.0.93; doc string of `read-file-name'

[Drew Adams]

1. The sentence about DIR belongs in a separate paragraph.  It has
nothing to do with PREDICATE.  (And the other args each get a
paragraph.)
 
2. The args should be described in order.  The paragraph for DIR should
be first among them.
 
3. For DIR, it is incorrect to say that it must be an absolute directory
name, since it can be nil.  Say something like this:
 
"If non-nil, optional second arg DIR must be an absolute directory name.
If nil, `default-directory' is assumed."
 
4. The description of DEFAULT-FILENAME should also be a separate
paragraph (and should come after the description of DIR).
 
5. For PREDICATE, it is incorrect to say it "must satisfy (funcall
PREDICATE NAME)": NAME is described nowhere.  Say something like this:
 
"If non-nil, optional sixth arg PREDICATE must be a function that
accepts a file name as its (first) argument.  Each completion
candidate and the entered file name must then satify PREDICATE."

In GNU Emacs 24.0.93.1 (i386-mingw-nt5.1.2600)
 of 2012-02-15 on MARVIN
Windowing system distributor `Microsoft Corp.', version 5.1.2600
Configured using:
 `configure --with-gcc (4.6) --no-opt --enable-checking --cflags
 -ID:/devel/emacs/libs/libXpm-3.5.8/include
 -ID:/devel/emacs/libs/libXpm-3.5.8/src
 -ID:/devel/emacs/libs/libpng-dev_1.4.3-1/include
 -ID:/devel/emacs/libs/zlib-dev_1.2.5-2/include
 -ID:/devel/emacs/libs/giflib-4.1.4-1/include
 -ID:/devel/emacs/libs/jpeg-6b-4/include
 -ID:/devel/emacs/libs/tiff-3.8.2-1/include
 -ID:/devel/emacs/libs/gnutls-3.0.9/include'