Update code to new proposal

1. Remove contactName from the region info/contract/DB;
2. Don't use "api/where" in the region API URL.
Replace the old search center with one that is based on the region

Also, replace the contact email with one from the region
Add debug logging statements, visible in BuildConfig.DEBUG only (i.e.,
not in release), that help track the logic of regions retrieval from the
Regions REST API, local caching of the regions data, and loading of
regions data at runtime.
Adds an AsyncTask (ObaRegionTask) that is triggered on app startup to
fetch the regions info after initial app install, and either auto-detect
what region should be used based on current location and the region
bounds, or show the user a list of regions to pick from if auto-detect
isn't successful.  Refactored some methods from ObaRegionsLoader into
RegionsUtils, since they were also needed in ObaRegionTask.