message: In .travis.yml, try caching the hypre builds.
  [skip appveyor]
diff: @@ -41,6 +41,10 @@ matrix:
  CODECOV=NO
  MFEM_TEST_TARGET=check
  NPROCS=2
  + cache:
  + directories:
  + - $HOME/../hypre-2.10.0b/src/hypre/lib
  + - $HOME/../hypre-2.10.0b/src/hypre/include
  #
  - os: linux
  compiler: gcc
  @@ -62,6 +66,10 @@ matrix:
  CODECOV=YES
  MFEM_TEST_TARGET=test
  NPROCS=2
  + cache:
  + directories:
  + - $HOME/../hypre-2.10.0b/src/hypre/lib
  + - $HOME/../hypre-2.10.0b/src/hypre/include
  #
  # Mac OS X
  #
  @@ -90,6 +98,10 @@ matrix:
  MFEM_TEST_TARGET=check
  NPROCS=4
  TMPDIR=/tmp
  + cache:
  + directories:
  + - $HOME/../hypre-2.10.0b/src/hypre/lib
  + - $HOME/../hypre-2.10.0b/src/hypre/include
  #
  - os: osx
  # osx_image: xcode7.3
  @@ -100,6 +112,10 @@ matrix:
  MFEM_TEST_TARGET=test
  NPROCS=4
  TMPDIR=/tmp
  + cache:
  + directories:
  + - $HOME/../hypre-2.10.0b/src/hypre/lib
  + - $HOME/../hypre-2.10.0b/src/hypre/include
  before_install:
  