las3_pub / predictable_parallel_patterns

Right now no work can be spawned, we simply have a proove of concept that we start up each thread, work for the master to finish and then synchronize back to the main thread.

See NOTES.md for details, basically std::thread can use dynamic memory allocation internaly and we want to prevent that.

The local storage per thread is only a pointer, this must be assigned AFTER the local storage object has moved to it's final location (e.g. on the stack of the caller). We might even change this a little further in the future to make the location of the state object more transparent.

The first draft of the internal threading component is currently only implemented using the c++11 std::thread, pthread support will be added next.

Seperate library from other parts of project (samples, playground, testing, ...). We still are in one 'toplevel' cmake project, so we can for exmaple compile everything (library and playground) in debug mode, for simple development.