Recognition model database update

[ToMadoRe]

The newest update of V4R uses a new file structure for the model database.

Instead of the old structure:
.../object_database/models/ (models)
.../object_database/recognition_structure_dir/ (training_dir)

the new structure merges these two folders into a common folder. This reduces the required parameters for the obejct recognizer to a single models_dir (-m) parameter. Objects that are modelled with the new version of RTM will automatically generate this file structure. To use existing object model datasets, you can use the tool convertOldModelDatabaseToNew to convert your models the new file structure.