Tensor reduction for zero Gram determinants

[vsht]

Dear FeynCalc users,

for a long time dealing with loop integrals that have zero Gram determinants was very problematic in FeynCalc.
In particular, tensor reduction didn't really work out of the box and one had to resort to tricks and external tools
such as Package-X.

With the latest commits to the development version these issues should be now mostly resolved. If you have calculations, that involve zero Gramians please have a look at the new summary here

https://feyncalc.github.io/FeynCalcBookDev/Extra/TensorReduction.html

I would be also glad to hear your opinions on the new functionality.

Cheers,
Vlad