Compilation fix for msvc2010
Compilation fix for msvc2010

Usage of back_inserter requires <iterator> header when using msvc2010

Change-Id: I92ee1649795ce0468ce337fc414eb0ca6e90c51e

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