Provide C++11 support

[Andrew Melim]

Look into whether we should utilize C++11 in gtsam.

Here is a table for compiler version support http://en.cppreference.com/w/cpp/compiler_support

[Abel Gawel]

I think feature/BAD branch (and maybe others) is using C++11 now. Is there a reason not to include compiler flags in CMakeLists?

set(CMAKE_CXX_FLAGS "-std=c++11 ${CMAKE_CXX_FLAGS}")

[Frank Dellaert]

No, feature/BAD does not use C++11. At least, not intentionally :-) There is a cost in that some of our partners have compilers and cross-compile to platforms where C++11 is still unsupported.

[Frank Dellaert]

Not for now

[Frank Dellaert]

Revisiting this for GTSAM 4. Compilers seem to have caught up with c++11, even on embedded platforms.

[Frank Dellaert]

Thoughts on throwing the switch @cbeall3 @abachrac @mikebosse ? To be backwards compatible, probably need to continue to use boost::shared_ptr....

[Frank Dellaert]

Switched to C++11 in PR #193