[C++11] Switch CMake to use C++11 by default! Next up, autoconf/make!
[C++11] Switch CMake to use C++11 by default! Next up, autoconf/make!

Now, please don't get too excited. I've just toggled the default to suss
out the last remaining bot problems. This does *not* mean we can all go
write lots of C++11 code yet. I at least want to let the dust settle
from the bots first.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@202542 91177308-0d34-0410-b5e6-96231b3b80d8

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