* Adds catch, cppunit, spdlog, tinyxml(1 and 2), google benchmark

Tinyxml comes in two flavors, 1 and 2. Each comes in several
versions... So they cannot be easily united into a single package.

* Use CMakePackage and friends, add copyright

Also eleminate debug/release variants, since it no longuer fits in the
CMakePackage format.

* Remove unnecessary url

* spdlog now has tagged releases

* Remove unnecessary url argument

* Fewer quotes in cmake args, because magic

* Incorrect base class for tinyxml