Change how composite parts are rendered

[dany-fu]

Having to fetch all referenced SBOL objects can significantly slow down SBH.
VisBOL should only render the subdesign if the user clicks on the composite object

[cjmyers]

Also, that rendering will happen naturally as it opens the page for the composite design to render that object. In other words, we should just render one level down at most.

[cjmyers]

Here is an example that is missing definitions for referenced components. When you encounter a CD with Components that are missing their definitions, then do not render the CD.

BBa_F2620.zip

[cjmyers]

Needs to be fixed in getDisplayList when converting SBOL to displayList