move working spec manifests into root

Author: tomcrane

demo/json/manifests/README.md

@@ -1 +1,3 @@
-This folder will contain work-in-progress draft sketches of potential JSON IIIF Presentation API specification manifest documents that describe 3D resources. These sketches represent actualized examples of what possible changes to the IIIF Presentation API specification could produce and support.  
+This directory contains draft IIIF Presentation API manifests encoding 3D content. These manifest drafts should be used in demo experiments achieving [IIIF draft manifest experiments](../demo/EXPERIMENTS.md). 
+
+These manifests may be identical or similar to manifests in [old-manifests](../old-manifests/). The difference between these files and those files is that these manifests may be updated over time reflecting the current thinking and work of the 3D TSG, while those are specific manifests generated at specific working meetings and are retained in the state in which they were originally generated. 

manifests/README.md

@@ -0,0 +1 @@
+This folder will contain work-in-progress draft sketches of potential JSON IIIF Presentation API specification manifest documents that describe 3D resources. These sketches represent actualized examples of what possible changes to the IIIF Presentation API specification could produce and support.