Add initial Dockerfile.
Add initial Dockerfile.

This is FROM thewtex/centos-build, which has an old glibc, but GCC 4.8.2,
which supports C++11. It also has CMake, gfortran.

Install the rendering dependency packages for VTK.

Clone and configure the tomviz superbuild. A complete build is a work in
progress.

thewtex/tomviz-docker