bug#20710: gitignore patterns for ps, html etc are too broad

[Glenn Morris <rgm@gnu.org>]

Package: emacs
Severity: minor

git ls-files -i --exclude-standard
admin/unidata/copyright.html
etc/ps-prin0.ps
etc/ps-prin1.ps
leim/MISC-DIC/CTLau-b5.html
leim/MISC-DIC/CTLau.html
nextstep/Cocoa/Emacs.base/Contents/Resources/Credits.html
test/indent/ps-mode.ps
test/indent/sgml-mode-attribute.html

Due to the presence of

*.html
*.ps

in .gitignore.

With bzr, those forms were the correct:

doc/**/*.ps
doc/**/*.html

A comment at the start of .gitignore says it avoids '**' for the sake of
old git versions.

Explicitly listing all current and future versioned html and ps files
for the sake of old git versions seems like a PITA.