Merge branch 'ticket31372_029' into ticket31372_035

## OS and compiler.

env:

  global:

    ## The Travis CI environment allows us two cores, so let's use both.

    - MAKEFLAGS="-j 2"

    ## The Travis CI environment allows us two cores, so let's use both.  Also,

    ## let's use the "-k" flag so that we get all of the compilation failures,

    ## not just the first one.

    - MAKEFLAGS="-k -j 2"

    ## We turn on hardening by default

    ## Also known as --enable-fragile-hardening in 0.3.0.3-alpha and later

    - HARDENING_OPTIONS="--enable-expensive-hardening"

  o Minor features (continuous integration):

    - When building on Travis, pass the "-k" flag to make, so that

      we are informed of all compilation failures, not just the first

      one or two. Closes part of ticket 31372.