Refactored all code related to the SPMV kernels to work with float.
Wrote a test that determines whether the compiler uses 64bit boundary alignments on std::pairs of uint64 and float.
Introduced functions that allow for conversions between different ValueTypes (e.g. from float to double and backwards).
Former-commit-id: 830d24064f
Added accessors for the SparseMatrix as I need access to the internal vectors.
Added a pure SPMV Kernel interface to check the kernel for errors.
Former-commit-id: 46e1449eeb