[Bro-Commits] [git/bro] topic/jsiwek/broker: Add support for building/linking broker within bro (7120098)

We should probably make the C++11 dependency more explicit, in
particular given that we want to prepare people for requiring it after
2.4.

One idea would be an explicit --enable-C++11 configure switch, which
--enable-broker would then either require, or activate automatically
along with itself. That would then also allow us to generally test Bro
compilation in C++11 mode.

In addition, it would be good to check at configure time that the
compiler indeed supports C++11; and if not, give an explicit erorr
message stating so (rather than failing compiling later). Maybe even
do that check without --enable-C++11 and warn people with older
compilers that Bro in the future won't compile for them anymore.

Nothing to do immediately, but to keep in mind as we get closer to the
next release.

Robin