Problem when calculating even dimention with python3

[dantengs]

We need to modify block2.py file that replacing '/2' with '//2'. Otherwise, there will be conflicts between floating-point numbers and integers. And for convinence, we can change the pathes（only file names） in bootstrap.py to relative path.

[cbehan]

Hi. Can you post a patch for blocks2.py to show what you mean? I haven't used this functionality in a long time myself because scalar_blocks has built-in support for block tables in even dimension. I just import those tables to pycftboot with the name argument.