tests: add `exec.skip` to compile but not execute tests

Signed-off-by: Jean Privat <jean@pryen.org>
tests: niti fully skips tests in exec.skip

Signed-off-by: Jean Privat <jean@pryen.org>
tests: add `cc.skip` to skip the C compilation of some programs

Exemple: unavailable C libraries.

Signed-off-by: Jean Privat <jean@pryen.org>
model: fatal error, instead of abort if more that one primitive class

Signed-off-by: Jean Privat <jean@pryen.org>
tests: add missing sav

Signed-off-by: Jean Privat <jean@pryen.org>
tests: a res without sav is OK if empty else is failed

This will simplify the addition of sav, that are required only if not
empty.
Moreover, a missing non-empty sav will triggers a FAIL instead of a
skip.

Signed-off-by: Jean Privat <jean@pryen.org>
tests: remove empty sav files

since now, empty res and no sav is an OK test

Signed-off-by: Jean Privat <jean@pryen.org>
tests: add more stuff from examples and contrib

Thanks to the cc.skip and exec.skip files, suitable tests are availables

Signed-off-by: Jean Privat <jean@pryen.org>