0.0.1.dev19

test ensure we are testing from a clean cache unless manual override

too many networking error related issues have snuck by due to the
local cache, so make sure we use a clean one by default each time we
test, it slows tests, but is very much worth it

this also exposes the continued issues with the completely hacked
implementation that we use for cache which doesn't even have the
ability to check to see whether the remote has changed or to indicate
that all caches should be refreshed in a way that is orthogonal to the
call sites of the functions that were decorated