Kwc_Abstract_Cards did not correctly format select

Kwc_Basic_LinkTag_Empty_Component was returned on recursiveChildComponents for
ImageEnlarge_LinkTag and resulted in error. The reason was Generator->_formatSelect
did not enter code for single parentData because parentData is always array,
even when only one element exists.
Also add tests for cards-generator
Merge pull request #181 from Ben-Ho/master-bugfix-linktag-empty

LinkTag_Empty does not have a getImageData() function, check if existing