message: feat(Docker): Bump VTK to 2019-01-03 master
  This include vtkJSONDataSetWriter.
  A patch is imported from ITK to fix the double-conversion build. This
  will be upstreamed later.
  The build also enables rendering support, but it has not been tested.
diff: @@ -3,9 +3,9 @@ MAINTAINER Insight Software Consortium <community@itk.org>
  WORKDIR /
  -# 2018-01-31
  -ENV VTK_GIT_TAG 5e4514f0eba6190c678c61fe25c9b2240135bdcf
  -RUN git clone https://github.com/Kitware/VTK.git && \
  +# 2019-01-03 + Emscripten patches
  +ENV VTK_GIT_TAG 6c0782ec65e2f911f108a02c7666d45337956cce
  +RUN git clone https://github.com/thewtex/VTK.git && \
  cd VTK && \
  git checkout ${VTK_GIT_TAG} && \
  cd ../ && \
  @@ -19,6 +19,7 @@ RUN git clone https://github.com/Kitware/VTK.git && \
  -DCMAKE_INSTALL_PREFIX:PATH=/install-prefix \
  -DBUILD_EXAMPLES:BOOL=OFF \
  -DBUILD_TESTING:BOOL=OFF \
  + -DVTK_NO_PLATFORM_SOCKETS:BOOL=ON \
  ../VTK && \
  ninja -j7 && \
  find . -name '*.o' -delete && \
  