bug#25771: 25.1; Emacs man page top line should mention 'editor'

[David R Forrest]

I was teaching a class of students about Unix/Linux/GNU and wanted to
show them their editing options with:

   man -k editor

I was surprised that Emacs did not shop up on the list.  I expected 
the results to include something like:

    emacs(1)                 - GNU project Emacs editor


I suggest editing emacs.1 to have the line:

   emacs \- GNU project Emacs editor


Thanks for great editor,
Dave