18650 improved spacer/holder

I was trying to use some printed 18650 spacers, but they were not optimal. The original injected molded design has 2 of the same tabs per side, and that makes the printed counterpart weaker so this module has:

Bigger tabs, alternated ones
Looser battery fit
Perfect fit for nickel metal grids

NOTE: Print two and test fit. Check out the comments, some people get a perfect fit, for some is too loose so there is some settings to tweak if is loose for you.