CMakeLists.txt: require C++-14

[pmeerw]

GCC 13.2 says

raw_pdb/src/Examples/ExampleTypes.cpp:1316:57: warning: lambda capture initializers only available with ‘-std=c++14’ or ‘-std=gnu++14’ [-Wc++14-extensions] 1316 | auto setName = [&setNameGlobal, name = names[i]](uint32_t typeIndex) -> bool {

[MolecularMatters]

Since the rest of the code builds with C++11, I'd like to adapt the example to make this work with C++11 as well.

[MolecularMatters]

Thanks to PR #86 , this should no longer be required.