variable to increase max allowed influencers per vertex on skinned mesh

## What problem does this solve or what need does it fill?

It seems to me like max influencers on a skinned mesh atm is 4 right now.

## What solution would you like?

set the max allowed influencers to 8 or 12. Preferably high? Depends on perf impact? 4 seems low.

## What alternative(s) have you considered?

have lower quality animations and longer setup times

## Additional context

Any other information you would like to add such as related previous work,
screenshots, benchmarks, etc.