Strip r from name of reversed boards in saved games.

Fixes #47 tileBoard() removes the leading r from common names that
aren’t r or R.
Changed common name handler in buildBoard()

Fixes #49 buildBoard() uses the same common name algorithm as tileBoard
to determine the differences between r, rr, rb, RB, RR, rRB, etc.
Merge pull request #48 from vasl-developers/reversed-board-tiling

Strip r from name of reversed boards in saved games.