Makefile: generates an error when VLDIR contains spaces
Makefile: generates an error when VLDIR contains spaces

vlfeat/vlfeat,CansenJIANG/vlfeat,hongzhili/vlfeat,cvfish/vlfeat,WangDequan/vlfeat,qubick/vlfeat,j-bo/vlfeat,richarddzh/vlfeat,richarddzh/vlfeat,vlfeat/vlfeat,WangDequan/vlfeat,rxl194/vlfeat,CansenJIANG/vlfeat,CansenJIANG/vlfeat,mylxiaoyi/vlfeat,richarddzh/vlfeat,mylxiaoyi/vlfeat,hongzhili/vlfeat,qubick/vlfeat,j-bo/vlfeat,vlfeat/vlfeat,mylxiaoyi/vlfeat,j-bo/vlfeat,erexhepa/vlfeat,hongzhili/vlfeat,erexhepa/vlfeat,mylxiaoyi/vlfeat,mylxiaoyi/vlfeat,rxl194/vlfeat,erexhepa/vlfeat,erexhepa/vlfeat,rxl194/vlfeat,WangDequan/vlfeat,cvfish/vlfeat,rxl194/vlfeat,vlfeat/vlfeat,rxl194/vlfeat,vlfeat/vlfeat,j-bo/vlfeat,rxl194/vlfeat,CansenJIANG/vlfeat,qubick/vlfeat,richarddzh/vlfeat,mylxiaoyi/vlfeat,erexhepa/vlfeat,vlfeat/vlfeat,WangDequan/vlfeat,hongzhili/vlfeat,cvfish/vlfeat,qubick/vlfeat,hongzhili/vlfeat,qubick/vlfeat,cvfish/vlfeat,cvfish/vlfeat,CansenJIANG/vlfeat,hongzhili/vlfeat,qubick/vlfeat,erexhepa/vlfeat,richarddzh/vlfeat,WangDequan/vlfeat,richarddzh/vlfeat,CansenJIANG/vlfeat,cvfish/vlfeat,j-bo/vlfeat,WangDequan/vlfeat