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/pushconstants/generate-spirv.bat

@@ -0,0 +1,2 @@
+glslangvalidator -V lights.vert -o lights.vert.spv
+glslangvalidator -V lights.frag -o lights.frag.spv

data/shaders/glsl/pushconstants/lights.frag

@@ -0,0 +1,37 @@
+#version 450
+
+#define lightCount 6
+
+layout (location = 0) in vec3 inNormal;
+layout (location = 2) in vec3 inColor;
+
+layout (location = 3) in vec4 inLightVec[lightCount];
+
+layout (location = 0) out vec4 outFragColor;
+
+#define MAX_LIGHT_DIST 9.0 * 9.0
+
+void main() 
+{
+	vec3 lightColor[lightCount];
+	lightColor[0] = vec3(1.0, 0.0, 0.0);
+	lightColor[1] = vec3(0.0, 1.0, 0.0);
+	lightColor[2] = vec3(0.0, 0.0, 1.0);
+	lightColor[3] = vec3(1.0, 0.0, 1.0);
+	lightColor[4] = vec3(0.0, 1.0, 1.0);
+	lightColor[5] = vec3(1.0, 1.0, 0.0);
+	
+	vec3 diffuse = vec3(0.0);
+	// Just some very basic attenuation
+	for (int i = 0; i < lightCount; ++i)
+	{				
+		float lRadius =  MAX_LIGHT_DIST * inLightVec[i].w;
+	
+		float dist = min(dot(inLightVec[i], inLightVec[i]), lRadius) / lRadius;
+		float distFactor = 1.0 - dist;		
+	
+		diffuse += lightColor[i] * distFactor;		
+	}
+			
+	outFragColor.rgb = diffuse;			
+}

data/shaders/glsl/pushconstants/lights.vert

@@ -0,0 +1,44 @@
+#version 450
+
+layout (location = 0) in vec3 inPos;
+layout (location = 1) in vec3 inNormal;
+layout (location = 3) in vec3 inColor;
+
+#define lightCount 6
+
+layout (binding = 0) uniform UBO 
+{
+	mat4 projection;
+	mat4 model;
+	vec4 lightColor[lightCount];
+} ubo;
+
+layout(push_constant) uniform PushConsts {
+	vec4 lightPos[lightCount];
+} pushConsts;
+
+layout (location = 0) out vec3 outNormal;
+layout (location = 2) out vec3 outColor;
+
+layout (location = 3) out vec4 outLightVec[lightCount];
+
+out gl_PerVertex
+{
+	vec4 gl_Position;
+};
+
+void main() 
+{
+	outNormal = inNormal;
+	outColor = inColor;
+	
+	gl_Position = ubo.projection * ubo.model * vec4(inPos.xyz, 1.0);
+	
+	for (int i = 0; i < lightCount; ++i)
+	{	
+		vec4 worldPos =  ubo.model * vec4(inPos.xyz, 1.0);
+		outLightVec[i].xyz = pushConsts.lightPos[i].xyz - inPos.xyz;		
+		// Store light radius in w
+		outLightVec[i].w = pushConsts.lightPos[i].w;
+	}
+}