Template release

This release is meant to be used as a C++ project template for future repositories.

What's in it?

The project currently demonstrates sample C++ examples of a singly linked list, binary search tree, sorting, and copy-and-swap idiom.

• CMake is used as the build system
• Doctest is used for unit testing
• GitHub Actions and Travis CI are used for CI/CD
• Code coverage results from CI/CD using Gcov/LCOV are uploaded to Coveralls
• Doxygen is set up for generating documentation

Windows CI currently fails for some reason, but since this project is intended to be a template, this should be okay.