fix: Try AppVeyor build with VS 2017 and Boost 1.69.0
fix: Try AppVeyor build with VS 2017 and Boost 1.69.0

schuhschuh/MIRTK,BioMedIA/MIRTK,BioMedIA/MIRTK,schuhschuh/MIRTK,BioMedIA/MIRTK,schuhschuh/MIRTK,BioMedIA/MIRTK,schuhschuh/MIRTK