PA: PA 56, PA 156, and PA 259 Realignments

[Markkos1992]

FYI, I am going to be making further realignments to PA 56 (may be multiple) and PA 259 in the future.

See links to branch commits below.

PA 56:  https://github.com/TravelMapping/HighwayData/commit/a1570b400fe0b731a85a15da6ea4d06b79eb81cc  (This is a realignment at Hiner Rd (HinRd) southeast of PA 259 for a recently completed bridge in 2018.)
PA 259: https://github.com/TravelMapping/HighwayData/commit/5a0190ac5ef4a45a65368f05a497f09b3f5d4ed4  (This was done due to a bridge being built over the Conemaugh River between 2004 and 2008 in a new location.  That was the best I got by looking at Historic Aerials.)

EDIT (9-9-2019):

PA 156: (https://github.com/TravelMapping/HighwayData/commit/f84147c86bb876084588be370ea0cbb42894b54b) (This was done because the route was not aligned correctly in Avonmore.)
PA 56: (Realignment 2) (https://github.com/TravelMapping/HighwayData/commit/41f8140e288eb1bfbb23ce8589c413a12e0907d8)  (This is a realignment between *OldPA56_C and *OldPA56_D north of US 22.)

[Markkos1992]

https://github.com/TravelMapping/HighwayData/pull/3129