Basic removal of unslotted elements - missing the integration of at least update_position into elements
SWT specs passing
Sample and specs run
Merge branch 'master' into remove-unslotted-elements
Allow star method with 4 arguments, fixes #508

* added specs
* used more general/easier hangling of default arguments
Add parent attribute and accessor to elements + shared spec

* also some formatting
Merge pull request #509 from PragTob/remove-unslotted-elements

Remove unslotted elements and add star method with 4 args