Change arrow design to be more clear

[ZMYaro]

Would you be open to considering a slightly more arrowhead shape (e.g., ⮟) for train arrow icons so it is clearer, at a glance, which direction a given arrow is pointing?

When a train is on a branch just past the split, it is difficult to tell at a glance whether the equilateral triangle icon is pointing diagonally along the branch, or is pointing up/down like the rest of the icons. In the example below, the circled train could be interpreted, at a glance, as either pointing along the curve toward JFK/UMass, or pointing down toward Braintree like all the other southbound trains.

[idreyn]

Sorry for the late response on this one. I totally see the problem, I would accept a PR for this.