message: Turn off cleaning and disable gcc-6 build
diff: variables:
  DO_BUILD: 'yes'
  DO_TEST: 'yes'
  - DO_CLEAN: 'yes'
  + DO_CLEAN: 'no'
  strategy:
  matrix:
  linux_gcc6:
  + enabled: false
  VM_ImageName: 'ubuntu-16.04'
  Compiler_ImageName: 'axom/tpls:gcc-6'
  CMAKE_EXTRA_FLAGS: ''
  