Test failure in test_packager.py

[gigony]

By #91 (fa4df1d#diff-5157658a12e346d2fe885a36d707672db33f8b43385a3596188a9cf06761f028R61) to avoid a type error, it now raises an error if the application path is wrong.
However, it causes a test failure in test_packager.py.

Please help update the test case so that it uses the actual (dummy) application code during packaging and test.

$ ./run test
_______________________________________________________________________________________________ test_packager _______________________________________________________________________________________________
tests/system/packager/test_packager.py:61: in test_packager
    packager_util.package_application(args)
../../miniconda3/envs/monai/lib/python3.6/site-packages/monai/deploy/packager/util.py:292: in package_application
    initialized_args = initialize_args(args)
../../miniconda3/envs/monai/lib/python3.6/site-packages/monai/deploy/packager/util.py:64: in initialize_args
    raise WrongValueError("Application from '{}' not found".format(args.application))
E   monai.deploy.exceptions.WrongValueError: Application from './tmp9xnttrcw' not found

[gigony]

Close this as this issue is resolved by #97