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/deferredmultisampling/debug.frag

@@ -0,0 +1,52 @@
+#version 450
+
+layout (binding = 1) uniform sampler2DMS samplerPosition;
+layout (binding = 2) uniform sampler2DMS samplerNormal;
+layout (binding = 3) uniform sampler2DMS samplerAlbedo;
+
+layout (location = 0) in vec3 inUV;
+
+layout (location = 0) out vec4 outFragColor;
+
+layout (constant_id = 0) const int NUM_SAMPLES = 8;
+
+vec4 resolve(sampler2DMS tex, ivec2 uv)
+{
+	vec4 result = vec4(0.0);	   
+	int count = 0;
+	for (int i = 0; i < NUM_SAMPLES; i++)
+	{
+		vec4 val = texelFetch(tex, uv, i); 
+		result += val;
+		count++;
+	}    
+	return result / float(NUM_SAMPLES);
+}
+
+void main() 
+{
+	ivec2 attDim = textureSize(samplerPosition);
+	ivec2 UV = ivec2(inUV.st * attDim * 2.0);
+
+	highp int index = 0;
+	if (inUV.s > 0.5)
+	{
+		index = 1;
+		UV.s -= attDim.x;
+	}
+	if (inUV.t > 0.5)
+	{
+		index = 2;
+		UV.t -= attDim.y;
+	}
+
+	vec3 components[3];
+	components[0] = resolve(samplerPosition, UV).rgb;  
+	components[1] = resolve(samplerNormal, UV).rgb;  
+	components[2] = resolve(samplerAlbedo, UV).rgb;  
+	// Uncomment to display specular component
+	//components[2] = vec3(texture(samplerAlbedo, inUV.st).a);  
+	
+	// Select component depending on UV
+	outFragColor.rgb = components[index];
+}