REVERT: Change to path explorer time limits.
VERSION: Increment to 11.30
CHANGE: Instead of resetting average timings when the path explorer is run, they are reduced, preserving the existing value, but making it less significant in comparison to new values when they are added. This should increase the temporal stability of the routing of passengers/mail/goods.
CHANGE: Industries will continue to demand goods based on the maximum in transit percentages even when their input store is full, to avoid intermittent supply when the lead time exceeds the time to consume. This does not properly respect the input storage (although it is used to calculate the maximum in transit precentages, so is not totally ignored): a possible solution would be to have the goods waiting at the final stop if the input storage is full, although this would take non-trivial programming effort for little if any actual economic effect.
CHANGE: Proper accounting of the input storage without causing intermittent demand for goods by combining the input storage and maximum in transit percentage into a single figure (still shown separately in the GUI).
FIX: int-hashtables were broken for uint64 keys, introduce hash_t::diff_type for differences of key_t values (adapted and backproted from Standard)
DE-REVERT: Path explorer iteration timing midpoint reduced again to 24.
CHANGE: Some log messages on loading a game will now only appear with a debug build.
CHANGE: Add a log message for when there are too many ships on a tile.