modules: support tests/samples/boards in modules

Generate options for sanitycheck to run tests and samples in modules.
Use the --sanitycheck-out <file> to generate a file that can be supplied
to sanitycheck on the commandline which will add additional testroots
and boards if the module does contain out of tree boards.

the module.yaml file now accepts the following:

samples:
  - path/to/samples
tests:
  - path/to/tests
boards:
  - path/to/boards

Signed-off-by: Anas Nashif <anas.nashif@intel.com>