Example showing standard linear algebra decompositions and solver

#### Issue Description

I'm in the process of adding ND4J to a Java linear algebra benchmark but I'm having trouble adding decompositions like, Cholesky, QR, SVD, Eigen, ... etc or solving for square or rectangular systems. Could examples be added for these operations? I was able to find example code for matrix multiplication and element-wise operations just fine. I can see the JavaDoc for these operations but it's fairly opaque. Thanks.