ENH: Started implementation of GPU LBFGS.
ENH: Added line search algorithm for more thuente solver.
ENH: Finished first draft of code for More-Thuente guaranteed sufficient descrease line search based on liblbfgs.
BUG: Fixed some compiler errors in the line search, still missing cubic and quadratic minimizer functions.
ENH: Refactoring for the new block sparse matrix vector.
ENH: Finished the implementation of BlockSparseMatrixVector.
ENH: Added implementation of lbfgs history.
ENH: LBFGS bug fixes.
ENH: bug fixes in the backtracking line search.
Merge pull request #1 from sudnya/gpu-lbfgs

Gpu lbfgs