templates update

[trel]

in this pr:

• external module handling for AVU-to-JSON conversion
• schemas on data objects
• recursion walks to the root
• schema location now 'url', 'irods', or 'local'

known todo:

• handle exceptions in 'irods' and 'local' schema gathering

[korydraughn]

Looking good so far.

Will review the BATs test later.

[trel]

have added issues for outstanding comments.

merging as is.