Moving backends code from examples/ to backends/ (step 2: moving vulkan cruft)

examples/example_glfw_vulkan/gen_spv.sh → backends/vulkan/generate_spv.sh

@@ -1,3 +1,6 @@
 #!/bin/bash
+## -V: create SPIR-V binary
+## -x: save binary output as text-based 32-bit hexadecimal numbers
+## -o: output file
 glslangValidator -V -x -o glsl_shader.frag.u32 glsl_shader.frag
 glslangValidator -V -x -o glsl_shader.vert.u32 glsl_shader.vert