If a *nix user wishes to build `pyrogenesis` with support for Valgrind
(such as
it is), then can do so by passing `--with-valgrind` to
`update-workspaces.sh`.
(They will need Valgrind installed and locateable via `pkg-config`.)
Reviewed By: sera, Stan
Fixes: #2904
Differential Revision: https://code.wildfiregames.com/D3646
This was SVN commit r25933.