Edward Z. Yang authored Oct 28, 2016 and Edward Z. Yang committed Oct 31, 2016

The key idea is that once we put PackageTests in its own package, we can
ensure that its Setup.hs is compiled with the same version of Cabal
library as package-tests is compiled with.  This means that LBI reading
will *always succeed* which is quite nice.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>