Selective build support for development or deployment

[svlugt]

A build of the repository will give a different result when build as stand-alone (for development and testing) or when included as sub-module. A stand-alone build should build the included examples, where a build of the cudawrappers when included as a sub-module in another project should only build the wrapper library.

[fdiblen]

We should have a CMake variable to build the examples.

If you build by running:

cmake -DBUILD_EXAMPLES=ON -S . -B build

It will compile the examples otherwise, the examples will not be compiled. This variable should be OFF by default.

[svlugt]

Yes, something like that.
I would prefer option(BUILD_TESTING "Build tests" OFF) as done here: https://git.astron.nl/RD/schaapcommon/-/blob/master/CMakeLists.txt#L14