Summary:
if env vars change between runs then the cache is invalidated, causing
configure to print a very specific error
by running a separate script to catch this error, the build can detect
and clear the cache when necessary to avoid having to manually disable
the cache when changing build settings
Depends on D6697
Reviewers: stefan_schmidt, bu5hm4n
Reviewed By: bu5hm4n
Subscribers: bu5hm4n, cedric, #committers
Tags: #efl
Differential Revision: https://phab.enlightenment.org/D6732
Mike Blumenkrantz