bin/bj: Remove un-necessary pystache import
bin/region: Remove some un-necessary imports
bin/render: Render region viewing files from templates

- Remove redundant HTML/JS from each region's /d/ directory and instead
  render them based on templates in /d/_templates/
- Compute the center of the map to view using the Shapely centroid point
.gitignore: Remove Solr pattern
bin/update: Render templates from www/_templates

- Move templates from www/d/_templates to www/_templates
- Change bin/update to run the 'templates' render command
bin/render: create templated parent dirs if necessary