build: return error value when executing script

make-ring is not returning the right exit status for any shell script
it executes.
By fixing its behaviour, this has highlighted an issue with the OSX
dependencies not being able to be updated with newer versions
This commit returns a fix value of 1 when a shell script returns an
error (exit status != 0) and make sure that every OSX dependency is
properly installed and updated

Reviewed-by: Stepan Salenikovich <stepan.salenikovich@savoirfairelinux.com>
Change-Id: Iced6d2eeb0d3028a3935e433c461fd20375e2d0b