bug#29262: 26.0; doc string of `find-grep-dired'

[Drew Adams <drew.adams@oracle.com>]

The doc string is not as clear as it could be.  It says:

Find files in DIR matching a regexp REGEXP and start Dired on output.
     ^^^^^        ^^^^^^^^^^^^^^^^^

What does it mean for a file to match a regexp?  This could easily be
misunderstood as the file name matching the regexp.

Please consider making the text clearer, e.g., along the lines of what
is said in the Emacs manual.  It speaks of files "that contain a match
                                                       ^^^^^^^
for REGEXP."

(And no need to repeat "regexp REGEXP".)



In GNU Emacs 26.0.90 (build 3, x86_64-w64-mingw32)
 of 2017-10-13
Repository revision: 906224eba147bdfc0514090064e8e8f53160f1d4
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --without-dbus --host=x86_64-w64-mingw32
 --without-compress-install 'CFLAGS=-O2 -static -g3''