NY: I/NY-878 exit numbers

[rickmastfan67]

Just curious, but why don't we have the 2 exit numbers on that route in each file?

I-678 -> Exit 1
JFKExpy -> Exit 2

Plus, on NY-878 separately, we should have a point @ 'North Hanger Road', due to NYSDOT considering that as 'Exit 3'.

[yakra]

It appears we didn't know about exits 1 & 2 when AltLabels (or hidden points, more likely?) were implemented. I-878 originally had 0 & 999.
http://github.com/yakra/HighwayData/commit/50d26082f69965eef8cd58af2edcde84157523de