Remove CERES_NO_LINE_SEARCH_MINIMIZER.

Now that the trust region minimizer depends on the line search
minimizer, conditional compilation of the line search minimizer
will lead to build breakages, so this option is now not available.

It is not expected to have as significant impact on users as the
amount of code in the line search minimization algorithm is
rather small to begin with.

Change-Id: I2aa6b6e6e3931b6428dbda654f14faf1ac6dd130
11 files changed