[Feature Request] Refactor Linear algebra service

**Is your feature request related to a problem? Please describe.**
The LinearAlgebra module is a big mess. Many not implemented functions, naming has to be unified, unmanaged access to LAPACK functions are sparse.

**Describe the solution you'd like**
Subproject FSharp.Stats.LAPACK (already existing as placeholder project) should contain the Lapack stubs and function access. LinearAlgebra.fs naming has to follow a convention. Drop MKL support and embrace netlib lapack as it is open source. Unify output types of managed and unmanaged versions of linear algebra functions

**Describe alternatives you've considered**
Support MKL alongside Netlib LAPACK