Correct higher resolution level 9/7 energy weight approximations

[boxerab]

It's nice to see this project getting the attention it deserves.

I notice that the higher level 9/7 energy weights / L2 norms are currently approximations, and that exact values can be found in the OpenJPH project here.

With permission from @aous72, these approximations could be corrected.

Ideally, these values could be calculated through some script

Thanks!