0.98.0

Well it's been over 14 months since 0.97.1 and a lot has happened with PortableGL in that time. Out of 177 commits, here are the highlights of changes/improvements:

• New standard shader library for convenience in common use cases. See ex1_std_shaders.c and ex2_std_shaders.c
• Support other texture formats (besides RGBA) by automatically converting them (configurable
• Support other vertex attribute types besides float (everything but double currently).
• New and improved wide line algorithm (AA lines aka GL_LINE_SMOOTH is still a TODO though)
• Early Z and Stencil testing when the fragment shader doesn't modify Z or discard any pixels
• Several API and quality of life improvements/conveniences
• Improved documentation (always more to do of course)
• Many more OpenGL functions and features supported including many OpenGL ES 2/3 features.
• Many many more regression tests, as well as new performance tests.
• Many many bug fixes and minor improvements/code cleanup (always more to do)

Thanks to Aeronix for sponsoring a huge chunk of those changes in Sep-Oct '23.