ELL sparse mat * dense mat almost done!
Removed remaining traces of matrix_kernel_class_deducer.hpp

Became obsolete with the integrated matrix kernel handling.
Autotuner : added light_tuning parameter for gemm
Generator : explicit cast of strides, starts to cl_uint

Should avoid compilation problems on some compilers
matrix_expression: Unified code base with vector_expression. Also removed a spurious debug output.

vector_expression was using the same functionality under a different name (result_of::reference_if_nonscalar<>).
As that is already extended for use with integers, this is now used in matrix_expression as well.
Added support for integer matrices for the host and CUDA.

OpenCL requires the full integration of element-wise OpenCL kernels for matrices first.
OpenCL kernel enqueue no longer tries smaller work group sizes, but instead errors out directly.

Otherwise, user kernels would observe pretty strange behavior if the work group size is invalid.
Generator : Fixed type safety when passing some arguments
Matrix elementwise operations no longer taken from auxiliary/, but part of the source tree.
Generator : added basic OpenCL to CUDA kernel translation. Can now dump valid CUDA kernel code
Dense Matrices: Basic BLAS levels 1 and 2 now also available for integers (except solves).

Only signed integers supported. Subtraction used for unsigned integers still buggy/undefined.
FFT: OpenCL kernels now integrated into source tree.
Generator : Removed empty leftover function
Added diag() for extracting a diagonal (or off-diagonal) of a matrix, or for generating a square matrix out of a vector with the specified (off-)diagonal.

Same functionality as MATLAB's diag() function. Supports all three backends.
Matrix: Added row(A, i) and column(A, j) to extract the i-th row and the j-th column of a matrix to a vector.

Increases compatibility with uBLAS. Note that A needs to be a dense matrix. only assignment to a vector supported.
Matrix: Added norm_frobenius()
Added element_pow() for vectors and matrices.

All three backends are supported.
Compressed (ELL) * Dense matrix multiplication
Generator : GEMM template : now unrolling fetch to local memory

5-10% performance improvement on AMD hardware.
Also uncommented some tests in generator_blas3-test
Benchmark : added double precision in generator_blas3 benchmark