Partial #3354 - build manylinux2010

[penguinolog]

Use manylinx2010 images to build manylinux1 and manylinux2010 at the same time.

[McSinyx]

Just curius, how is that possible with such simple change? I'm currently using cibuildwheel for my personal project but want to know how things work.

[penguinolog]

Manylinux2010 is not so far from manylinux1, so manylinux2010 for compatibility reasons also making manylinux1 wheels.
Manylinux2014 is different: it Centos 7 based and have different versions of system libraries, so it not able to build wheels for old systems.

[scoder]

Works for me, but doesn't seem to have a benefit for now. It just doubles the number of generated "manylinux" wheels.

[penguinolog]

technically manylinux2010 uses newer libraries (centos6 instead of centos5), old name is served for old pip compatibility reasons.
Centos5 is already "dead", so manylinux2010 is more actual.

[scoder]

Thanks for bringing this in. I think it's good to make the switch to at least the somewhat newer 2010 wheels.