Move shaders into glsl and hlsl directories

Move `data/shaders` to `data/shaders/glsl`
Move `data/hlsl` to `data/shaders/hlsl`

Fix up shader paths in the cpp files to point to the new glsl location.

`data/shaders/hlsl/compile.py` still overwrites the glsl .spv files (for
now).

Issue: #723

data/shaders/glsl/occlusionquery/mesh.vert

@@ -0,0 +1,38 @@
+#version 450
+
+layout (location = 0) in vec3 inPos;
+layout (location = 1) in vec3 inNormal;
+layout (location = 2) in vec3 inColor;
+
+layout (binding = 0) uniform UBO 
+{
+	mat4 projection;
+	mat4 modelview;
+	vec4 lightPos;
+	float visible;
+} ubo;
+
+layout (location = 0) out vec3 outNormal;
+layout (location = 1) out vec3 outColor;
+layout (location = 2) out float outVisible;
+layout (location = 3) out vec3 outViewVec;
+layout (location = 4) out vec3 outLightVec;
+
+out gl_PerVertex
+{
+	vec4 gl_Position;
+};
+
+void main() 
+{
+	outNormal = inNormal;
+	outColor = inColor;
+	outVisible = ubo.visible;
+	
+	gl_Position = ubo.projection * ubo.modelview * vec4(inPos.xyz, 1.0);
+	
+    vec4 pos = ubo.modelview * vec4(inPos, 1.0);
+    outNormal = mat3(ubo.modelview) * inNormal;
+    outLightVec = ubo.lightPos.xyz - pos.xyz;
+    outViewVec = -pos.xyz;
+}