refactor testing

Split testing into general testing files directly in t/, and dist
specific testing into separate directory with a script to check it.
use small bash tap implementation
Module::Build testing
move --auto handling into its own file
more outputs from auto command
refactor ./Build override
add --debug flag and provide some debug messages
only override needed bits (EUMM vs MB)
more diagnostics on dist building
test verbose
prioritize Module::Build for dist building
auto install configure deps for Module::Build during dist build
Module::Build needs a manifest step too