* Implement PNG & arb texture replacements
Fixes#119
For arb textures it's just making sure the file parsing can handle them. Idk if we need to do something special for it.
* Allow non-mipmapped textures to be replaced by mipmapped textures
Some of Henriko's textures (like the cuttable grass) rely on this.
The mipmap bool is no longer part of the runtime key.
* Make texture name the texture replacement key
Might as well? Helped me debug some stuff
* Oops that broke it bad
* libpng instead of spng
* I did it again
* Update libpng fetch
* Add zlib fetch
* Forgot to set the hash
* Add zlib redirect
* Add INCLUDE_DIR(S) to redirect
* Prefer shared for libpng
* Set CMAKE_FIND_PACKAGE_TARGETS_GLOBAL
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Co-authored-by: Luke Street <luke@street.dev>
Pieter-Jan Briers