Create some initial code for discussion

[HendrikTolman-NOAA]

For the record, I am finding my way now to use the projects and issue features in GitHub. The starting point of this is issue #13, which is building the "template" version of the model. This template version defines the general data structures and management architecture, but not yet any of the solvers. However, the high-level DESIGN of the solver is critical to set up the template version.

The initial-initial development got a little ahead of the project planning as I was learning the ropes with both GitHub and C++. Since I am a tactile learner, I benefitted from having some actual code to feel my way. Having this code available also worked well to jump-start discussions with the intended development community. Now that I have my feet wet, I intend to go to a discuss-first build later approach to give the community more opportunity for producing input.

This first step was implemented in PR #19. This PR has lead to several additional issues. As none of these are in the critical path for developing the initial template model they are treated as independent issue:

• Issue Settle standard for in-line comment-line documentation, including numbering of comments #22
• Issue Refactor initial YAML approach and add point and field input request processing #23
• Issue Date and time management service routines could benefit from modernization. #29