fix TestGraphPath

Route from/to stops instead of depart/arrive vertices.
Check for sequence of stops visited, not path length.

Several tests were failing due to path length differences.
I believe this is because we are no longer removing "useless"
dwell edges, which increases the path lengths.
remove OTPPriorityQueue interface and accompanying factory interface

use of pluggable factories makes the code less clean and readable.
we only ever use the BinHeap implementation because it represents a
good trade-off between speed and flexibility. it is also simpler,
smaller, and at least as fast as a Fibonacci heap, which gains lower
theoretical complexity at the cost of space and code complexity.

Also simplified the priority queue tests, which were being used
as a speed comparison.
NodeTrackerTest: reduce output and increase speed
fix testRouting

1. use stop vertices not arrive/depart
2. check sequences of stops rather than exact path length