Add a very simple unit test for the Weka Segmentation

Signed-off-by: Ignacio Arganda-Carreras <ignacio.arganda@gmail.com>
Add a more sophisticated test for the Weka Segmentation

This test segments the Bridge example; unfortunately, it runs much
slower and needs an example image with known-good segmentation.
Therefore we provide a main() method that downloads the sample and
generates the known-good segmentation. The corresponding test is skipped
if either image is missing.

Signed-off-by: Ignacio Arganda-Carreras <ignacio.arganda@gmail.com>
Cosmetic changes in the Trainable Segmentation

Signed-off-by: Ignacio Arganda-Carreras <ignacio.arganda@gmail.com>
Make scijava-common a dependency of the Trainable Segmentation

Signed-off-by: Ignacio Arganda-Carreras <ignacio.arganda@gmail.com>
First stab at a FeatureService based on scijava-common

Signed-off-by: Ignacio Arganda-Carreras <ignacio.arganda@gmail.com>
wip: adding new classes and methods to be able to create the features from a FeatureService, following Curtis new architecture.