Fixed bug appearing in kernels after a GEMV based one
* Generator : Fixed #include issue
* Generator : Added math function sign()
* Generator : Fixed missing #ifdef on random_vector and random_matrix
* Generator : Added test for kernel segmentation
* Generator : separated SAXPY for vectors and matrices
Merge branch 'master' of https://github.com/viennacl/viennacl-dev
Generator : Rewrote packing policies