Warning for non-existence of unit-threaded flag is back, but now it also checks to see -f is being used. As it should've all along
Option --nodub now controls whether to run dub. By default it fetches unit-threaded to be able to run the tests
dtest now prints the filename alongside the instructions to use it
Converted all calls to algorithms to use UFCS
Executes dub when needed even if -f option used. Sets -u correctly to dub directory
Documentation in README.md and online help reflect how to use -u and --nodub
Supposedly should work on Windows now as well