Add examples shroud user projects?

[kennyweiss]

It would be helpful to potential users if shroud had two simple standalone example projects (e.g. with only one or two functions):

• A cmake (or blt) C++ project that generates Fortran and Python bindings
• A make-based C++ project that generates Fortran and Python bindings

These could help users understand how to set up shroud within their project.

They could be placed in a new top-level directory, e.g. <shroud>/examples, described in the user docs and CI tested (e.g. through travis).