Some repaired and some new tests.

Bumped httplib version to v0.26.0. Changed FetchContent for nlohmann::json.

Changes that were necessary due to the introduction of the new globals.hpp file.

A lot of changes to fix some bugs and add functionality.

New interface (abstract class).

Some changes to logging statements.

Extended to support prompts.

ProgramOptions extended to support log file names.

Some refactorings and other changes.

New argument to specify a logfile name added.

New file, that contains very global common data.

Some refactorings.

Some minor changes to logging.

Member added that can hold the SysML v2 API Server URL.

spdlog added and some other minor changes.