doc: more layout adjustments
doc: more layout adjustments

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