Method created for parent -> child relationship

[apric0ts]

Created method to define parent child structure by finding which components are connected.
Structure displayed in the preview text box in Fusion 360 UI
Resolves #29

[cadop]

Could you double check that this works with nested joints/components and then have a checkbox to use this method instead of the user-defined one?

[apric0ts]

The checkbox looks like this, if check box is clicked then it uses this method instead of user defined

Regarding the nested joints/components,

The nested joint/component error seems to be a problem even without the automatic building of joints, it seems that the joint is not found at all when iterating through the root's joints in both the user-defined hierarchy and the automatically generated hierarchy.

The issue is caused when the joint is connected to a nested component (component within a component).

Here is what the error looks like

Rev1 is a revolute joint connected to a nested component. The joint is not found in self.root.joints that is used to generate joints within _joints method in Configurator class of parser.py.

I have attempted something like: adding the root joints to a list, then checking the root for child occurrences ( if self.root.childOccurrences: ) and adding the joints connected to those child occurrences to a list of all joints, however not sure if this approach will work.

In the URDF, both the joint and the whole (nested) component that the joint is connected to are missing/not generated.

This seems to be an issue somewhat related to issue #33 . I will open another issue regarding this.

I'll add what I have done to this PR shortly, everything seems to work when components are not nested within the top level components, but when nested, it does not work.