tests: Use automake's tap driver

tap-driver.sh is copied from my automake installation.

Signed-off-by: Robin Sonefors <robin.sonefors@op5.com>
test: Run t-tap tests though tap prover

This means we'll once again be able to get under travis' 10 000 line
output restriction.

Signed-off-by: Robin Sonefors <robin.sonefors@op5.com>
tests: Remove testall.sh wrapper for t tests

Use automake's tap driver instead.

Signed-off-by: Robin Sonefors <robin.sonefors@op5.com>