v0.0.0-5248-gc3649e042

Description how to get release: use standard shell tools.

Don't put the user through the hassle to first have to install
some scripting language when they can use common tools available
in any shell.

Also set 'silent' flag on curl to adhere to the no-news-are-good-news
Unix principle.

PiperOrigin-RevId: 642802671