This is part of my quest to replace all unneeded std::shared_ptrs for
std::unique_ptrs to improve performance, since there is no need for
reference counting for pointers that are uniquely used. I also had to
change the first parameter of Lexer::assign_parent_location to a
std::unique_ptr<Lexer>& so that it can accept the new result of
make_lexer.
Planning to use LLVM to make stuff easier. Also, moved the random
sapphire stuff to actual examples in an actual examples/ folder. Also
started a standard library even if the compiler is not ready, because
why not?? Also, it helps the examples.
