Simplified persistent intersection homology calculation
Simplified persistent intersection homology calculation

* Removed manual specification of reduction algorithm
* Removed manual reduction of boundary matrix
* Using proper persistence diagram creation

Some TODOs:

* The interface for specifying perversities is still off by one
* The nomenclature is not correct: the input spaces, marked by `X` in my
  implementation, are not the actual *strata* of the function

Submanifold/Aleph,Submanifold/Aleph,Submanifold/Aleph