wcst_import should report an error on invalid option

[Dimitar Misev]

If a user specifies an option that is not recognized by wcst_import, then wcst_import should throw an error instead of ignoring the option.

Furthermore, validating options seems to be duplicated in each recipe now. For common options this should be refactored into methods in the BaseRecipe class.

The code to validate ingredients files exist in several recipes files, method validate() in applications/wcst_import/recipes/*/recipe.py

[Dimitar Misev]

Perhaps something like this would be useful for the validation: ​https://pypi.org/project/jsonschema/

[Bang Pham Huu]

The code to validate ingredients files exist in several recipes files, check validate() in recipe.py:

applications/wcst_import/recipes/*/recipe.py

[Dimitar Misev]

I'm getting this error now:

The jsonschema package is not installed, ingredient file validation will be skipped.           To enable validation please install jsonschema (sudo pip install jsonschema)
An error has occured in the execution of the program. Error Message: local variable 'jsonschema' referenced before assignment
Stack Trace: Traceback (most recent call last):
  File "/home/dimitar/rasdaman/enterprise/src-install/share/rasdaman/wcst_import/wcst_import.py", line 161, in main
    ingredients = decode_ingredients(read_ingredients())
  File "/home/dimitar/rasdaman/enterprise/src-install/share/rasdaman/wcst_import/wcst_import.py", line 144, in decode_ingredients
    validate_ingredients(ingredients)
  File "/home/dimitar/rasdaman/enterprise/src-install/share/rasdaman/wcst_import/wcst_import.py", line 90, in validate_ingredients
    jsonschema = import_jsonschema()
  File "/home/dimitar/rasdaman/enterprise/src-install/share/rasdaman/wcst_import/util/import_util.py", line 68, in import_jsonschema
    return jsonschema
UnboundLocalError: local variable 'jsonschema' referenced before assignment

This case (when jsonschema is not installed) should be a warning, not an error.

[Dimitar Misev]

"__comment__" attributes should also be allowed anywhere in the ingredients