Tests: Disabled non-symmetric eigenvalue routines.

These routines need substantial refactoring anyway (very experimental)
and are not even documented properly. Include them back into test suite
only after the refactoring is completed.
compressed_matrix: Improved documentation.

Resolves #95. A completely typesafe interface to .set() is not possible,
because OpenCL is not fully typesafe.
Disable coveralls.

lcov takes much too long making the travis builds time out and fail.
Cleanup: Removed unused source files.

Old generator tests and OpenCL random number generation. Both superseded.
Merge pull request #110 from d-meiser/disable-coveralls

Disable coveralls. Takes too long to run and hence fails.
inplace_solve, dense: Simplified code and improved performance.

Resolves #6. A little bit of input-dependent tuning is certainly possible,
yet the overall control flow is now fixed. Performance largely dependent
on the performance of matrix-vector and matrix-matrix products, respectively.
(sliced_)ell_matrix, hyb_matrix: Added overload for STL-emulated sparse matrix.

Now a user can directly provide std::vector< std::map<IndexType, NumericType> >
to populate the sparse matrix. This was already possible for the other sparse matrix
types.
Self-assignment: Added test and fixed all bugs found.

Problems were only found in the matrix-times-matrix case.
Resolves #2.
compressed_matrix: Implemented CSR-adaptive in CUDA and OpenCL.

See paper "Efficient Sparse Matrix-Vector Multiplication on GPUs using the CSR Storage Format"
by Greathouse and Daga, presented at SC 2014.
CUDA: Fixed compilation error in triangular solve kernels.

Introduced by 0ba719f3ec0eb284f9e3d4faea9aadb77de0141a.
Direct solve: Fixed errors obtained after resolution of self-assignment problems.
Visual Studio 2012: Fixed performance warnings and a test compilation error.

Warnings were due to conversion of floats to bools.
Updated version to 1.6.1.
Doxygen: Fixed warnings.
Changelog: Added notes for 1.6.1 release.
Changelog: Fixed incorrect co-author name of CSR-adaptive paper.
Tests: Fixed incorrect test code in libviennacl-blas1.
CUDA: Cleanup of CSR-adaptive implemenentation, adjustment of block sizes.

Based on experiments on a GTX 470. Kepler and Maxwell GPUs might
behave differently.
OpenCL: Added CSR-adaptive for pipelined iterative solvers.
CUDA: Added CSR-adaptive to pipelined iterative solvers.