pt_assistant: recompile for compatibility with JOSM r17867

Signed-off-by: Taylor Smock <tsmock@fb.com>

see https://josm.openstreetmap.de/ticket/19851

Add contribution guidelines and share IntelliJ run configurations for `runJosm` and `dist` tasks

This also replaces the distance calculation between the current way to the next way by a new method (min distance to either first or last node instead of the distance to the average of the first and last node).

Reimplement methods for finding the way segment nearest to a node and determining on which side of a way a node lies.

The methods are now in a new utility class, so for these things you no longer need to create or obtain instances of `StopToWayAssigner` or `PTRouteDataManager`.

Fixes https://github.com/JOSM/pt_assistant/pull/21

This is a cherry-picked version of 407757e8...50d18b78ec63983822d1ea609d89d2c0f032c567

Fixes https://github.com/JOSM/pt_assistant/pull/20 .

Added a way to remove members with specific roles

Added a broken method to add ways adjacent to pt=platform or discretely mapped highway=bus_stop

 If a user requests to sort the stops in a route that is not public_transport:version=2, the first question is whether to add the tag. Then it asks whether the user wants to remove all the oneway ways. Then it creates a new route relation for the return trip. (This might not be used). Then it orders the stops in the original route relation
If there are stop/platform members with *_backward or *_forward, they are removed in the corresponding route relation.
Then it orders the stops in the original route relation (this happens after removing stops/platforms)
Then it asks the user if they want to create route relation for the return trip, if so it uses the previously created route to actually create such a route relation.
It also asks if the user wants to create a public_transport=route_master relation, and adds both route relations to it.