The test target is now defined in the common `Makefile.include`.
This removes the warning
Makefile: warning: overriding recipe for target 'test'
Makefile.include: warning: ignoring old recipe for target 'test'
For the RIOT port of Lua, the module loader has been more or less
rewritten to allow for easily integrating source modules defined in static
arrays and C modules embedded in the application.
So far the loader had not been tested (and a bug was found). This test
should give a bit more certainty that the RIOT integration works as it
should.
