Port the python2.7 local settings overrides to the python3.6 directory
structure.
Move all local_settings.py overrides into _05_snap_tweaks.py as part
of troubleshooting some remaining problems. Everything is more
organized and functional now :-)
Added selenium tests.
Change-Id: I54923e1dc9c7ffa47c2ef6fb90ea9d224b0d2eee
0b4c7a22a3