* Fix test cache to consider MLD executable changes
Currently the test cache is not invalidated if changes to
osrm-partition or osrm-customize executables. This is problematic
when these executables make breaking changes to the data format.
We fix this by including both in the list of executables that
can invalidate the test cache.
* Executables use hyphens
Upgrades the build environment to Node 10, which let's us pull down some security fixes in package dependencies that were unfixed in Node 4.
Also removes Node 4 and 6 binary publishing which were almost never used (20 downloads out of 50,000).
Fixes https://github.com/Project-OSRM/osrm-backend/issues/5312
