LRDOCS-383 improve namespacing of dist ZIP files.

This change is needed so that our 6.2 asset imports do not conflict with the 6.1 assets imports and future imports. Note, particularly, the image file folder is based on the zip file name.

Important: This change is for trunk only. It is NOT for the 6.1.x branch.

Thanks.

@codyhoag Thanks for doing this.