avocado.core.exceptions: Make TestSetupFail an ERROR

It is easier to show when a test actually failed, or
we were not able to successfully set the test up.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
avocado.test: Raise TestSetupFail on both setup and cleanup

Since both can possibly fail and mask the actual test
results.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
avocado.core.exceptions: Avoid avocado crashing on unknown error status

Since someone might want to be funny and raise those
exceptions, it is safer to make them to return "FAIL"
instead of "NEVER_RAISE_THIS", so avocado does not
crash.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
avocado tests: Add 3 functional avocado tests

They raise the following exceptions:

1) TestError (failure)
2) TestNAError (skip)
3) TestWarn (failure)

The corresponding functional tests for them go
in the Travis CI file.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Merge pull request #58 from avocado-framework/new-tests

Add new avocado Functional Tests