Enable -Werror for CI builds (was ACTS-493)

Original author Paul Gessinger-Befurt @pagessin

This will fail the build if any warnings are raised during compilation. The flag is only added in the CI, so locally you can build and ignore the warnings.

See ACTS-454, which will be fixed by this.

Edited Mar 27, 2019 by Moritz Kiehn

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information