gl_basic: Add a --robust option
gl_basic: Add a --robust option

If set, gl_basic requests a robust context.

Signed-off-by: Chad Versace <a557f7f75bf28dc19ac99107f5cc7cd6b3fbdb1a@intel.com>

fjhenigman/waffle,dcbaker/waffle,chadversary/waffle,chadversary/waffle,waffle-gl/waffle,dcbaker/waffle,waffle-gl/waffle,waffle-gl/waffle,fjhenigman/waffle,dcbaker/waffle,chadversary/waffle,fjhenigman/waffle,waffle-gl/waffle