Updating docs to include Windows options for SuiteSparse.
Updating docs to include Windows options for SuiteSparse.

- A number of users are now successfully using the
  suitesparse-metis-for-windows project to build Ceres with SuiteSparse
  on Windows.
- Also fixing missing requirement for sphinx_rdm_theme if building
  the Ceres docs.

Change-Id: I1a36c13166f96743557de2ac3b7c9b84531d1f24

ysonggit/ceres-solver,timfel/ceres-bin,whuaegeanse/ceres-solver,stonier/ceres_solver,timfel/ceres-bin,timfel/ceres-bin,stonier/ceres_solver,stonier/ceres_solver,kartikkumar/ceres-solver,whuaegeanse/ceres-solver,ysonggit/ceres-solver,entylop/ceres-solver,kartikkumar/ceres-solver,whuaegeanse/ceres-solver,entylop/ceres-solver,kartikkumar/ceres-solver,stonier/ceres_solver,whuaegeanse/ceres-solver,DougFirErickson/ceres-solver,DougFirErickson/ceres-solver,ysonggit/ceres-solver,DougFirErickson/ceres-solver,DougFirErickson/ceres-solver,ysonggit/ceres-solver,timfel/ceres-bin,kartikkumar/ceres-solver,entylop/ceres-solver,entylop/ceres-solver