fix: gpujs#590 add Kernel.onActivate

- which is called after gpu.js switches kernels based off need
fix: Consistent error message for values that are not defined
fix: Add recompiled kernels to gpu.js kernels property and test
fix: Move texture deleting to within the GLKernel Texture implementation
fix: Add Texture.clear as an abstract method on the base Texture
fix: Bump and build

fix: gpujs#585 check for inaccurate results for very small kernel

fix: gpujs#585 add features.isSpeedTacticSupported and tests

fix: gpujs#586

fix: gpujs#572 excessive calls, reuse textures

feat: introduce WebGL._replaceOutputTexture and WebGL._replaceSubOutputTextures to cut down on resource usage
feat: All supportable Math.methods added
fix: Safari not able to render texture arguments
feat: CPU gets a pipeline that acts like GPU with/without immutable

fix: Build and build

fix: Clearing cloned textures produces new internal copy when multi r…

…eferences

fix: security

fix: Don't call `beforeMutate` if immutable and unit test

fix: Don't call `kernel.updateTextureArgumentRefs` if kernel is mutable

Merge branch 'develop' of https://github.com/gpujs/gpu.js into develop