SunPro: Record support for C++14 features by SunPro 5.{14,15}

SunPro 5.15 supports `-std=c++14` and several C++14 features.

SunPro 5.14 accepts `-std=c++14` but does not update its definition of
`__cplusplus` or any other macro to distinguish it from `-std=c++11`,
so we need to blacklist a couple features that do work but that we
cannot report for that version.  We can still support `cxx_std_14`.

Co-Author: Robert Maynard <robert.maynard@kitware.com>
22 jobs for sunpro-cxx14-features