This commit adds the RH/ZO perspective function. It does so in the new
file `cam_rh_zo.h` and further refactors the LH variant into new file
`cam_lh_zo.h`. This creates some churn in the tests and configuration
files as new test files were added as well, and all these changes found
their way into the build files.
Tests passing on Linux.
This commit adds the function `glm_perspective_lh_zo`, modelled on the
implementation of glm_perspective, but amended to provide a left-hand
coordinate system expected by DirectX, Metal and Vulkan (per the GLM
project's `glm/detail/setup.hpp`). It uses a clip-space of zero-to-one.
The function is tested against a longhand version of the algorithm it
seeks to implement as well as against the output of the GLM project's
`glm::perspectiveLH_ZO` function. This commit adds a new subdirectory
`test/glm_cmp` which contains a basic CMake file and `main.cpp`. An
interested user should link or copy or clone the GLM project into this
directory. The `main` function can be used to print the reference data
used so others can verify behaviour in the future, or add new literal
reference values.
