Description of the problem / feature request:

Today it is not possible to add multiple --bazelrc options to the command line.

Feature requests: what underlying problem are you trying to solve with this feature?

We have some default options in a common bazelrc file that is used in many workspaces since the options are needed to build for our platform.
Today we need to add those options in all user .bazelrc WORKSPACE files.
If it would be possible to add multiple --bazelrc options on the command line we could have one rc file for the common parameters and still be able to use other bazelrc files for the user projects.

What operating system are you running Bazel on?

linux

What's the output of bazel info release?

0.20.0

Have you found anything relevant by searching the web?

No

Any other information, logs, or outputs that you want to share?