DISCONNECTED_ROUTE cases can reverse the wrong routes

[yakra]

TravelMapping/DataProcessing#610
Note the old commits shown in the OP. We won't see this on production noreaster right now.

https://github.com/TravelMapping/HighwayData/blob/2decc64/hwy_data/_systems/indnh_con.csv#L14
indup.nh044-e gets reversed by siteupdate.
indup.nh044-w gets reversed by showroute.

We should get the same behavior from siteupdate and showroute.
Let's not change showroute just yet though; I'll be changing what siteupdate does soon.

[yakra]

DISCONNECTED_ROUTE behavior in siteupdate was changed in TravelMapping/DataProcessing#617.

[yakra]

To save us from having to replicate the complex logic of the DataProcessing side on the Web side, we could include a new isReversed column in the routes DB table.

I don't expect to be rewriting that in the future, but this can save our butts in case it does happen.