added Python 3.7 to .travis.yml
added Python 3.7 to .travis.yml

ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/RepairBox,ChrisTimperley/RepairBox,ChrisTimperley/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/RepairBox,ChrisTimperley/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/RepairBox,ChrisTimperley/RepairBox,squaresLab/RepairBox,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/AutomatedRepairBenchmarks.c,ChrisTimperley/RepairBox,ChrisTimperley/RepairBox