ENH: Adding the ability to ignore items
Also added the following:
- Ability to indicate that an Attribute's name should not be editable via the bool Property: smtk.extensions.attribute_view.name_read_only
- qtGroupItem will not display it's children frame if it have no relevant children
- Modified Attribute/Item isRelevant methods to optional test for read access
- Expanded Resource/Component Properties to include bool, int, vector of bools and vector of ints
- Added example of a sbt file where group items have no relevant children
- Added a test for new isRelevant and isIgnored functionality