Thanks a lot to @asalzman for his help.

xDistVector is now a template class: it can hold any numerical types
such as float, double, std::complex<double> etc...

By default, double values are assumed, so that in your code, you should
only need to replace xDistVector by xDistVector<>

In addition, xlinalg::xCPPBlasDef<T> is introduced in order to simplify
blas calls, and allow easy template blas code. All the available calls
are listed in xBlasDef.h. Today, float, double and complex<double>
values are considered (not with feature parity).

xCSRVector, xDenseMatrix etc... are modified to use xCPPBlasDef.

Update xDistVector atomic test case to float/double/complex values