Currently /trip supports finding round-trip routes where only the
start or end location is fixed. This PR extends this feature to
non-round-trip requests.
We do this by a new table manipulation that simulates non-round-trip
fixed endpoint requests as a round-trip request.
Does not run the nodejs tests in sanitized builds. We'd have to
export LD_PRELOAD='/usr/lib/x86_64-linux-gnu/libasan.so.2'
the asan lib. But it seems like our Clang from mason does not like the
system's libasan. Also we'd need a suppression file for v8 and node.
