Abderrahim Kitouni authored Oct 28, 2018 and Valentin David committed Nov 19, 2018

cmake sometimes misinterprets relative paths as relative to the current directory
if this is not specified. See freedesktop-sdk/freedesktop-sdk#431

adjust tests/format/variables.py accordingly.

plugins/elements/cmake.yaml: always specify variable types

Closes #761

See merge request !947

Sandbox errors (like missing host tools) are dependent on the host
system and rarely on what is actually done.

It is therefore better to not cache them as they are subject to
change between two runs.

Also add test to ensure sandbox failure are not cached

Reverse the way we were handling caching by only caching
when we know it's a problem with the build or the build is a
success in order not to cache transient errors.