Fix a dead link in doc. The original link is not available any more. Change-Id: I0d47f5e05d80973bc29deb377ccec814f555e3ef
Ceres Solver is an open source C++ library for modeling and solving large, complicated optimization problems. It is a feature rich, mature and performant library which has been used in production at Google since 2010. Ceres Solver can solve two kinds of problems.
Please see ceres-solver.org for more information.