try to fix KLU include and make appveyor flag build failures correctly
try to fix KLU include and make appveyor flag build failures correctly

FFroehlich/AMICI,FFroehlich/AMICI,AMICI-developer/AMICI,AMICI-developer/AMICI,FFroehlich/AMICI,AMICI-developer/AMICI,FFroehlich/AMICI,AMICI-developer/AMICI