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/tessellation/passthrough.tese

@@ -0,0 +1,27 @@
+#version 450
+
+layout (triangles) in;
+
+layout (binding = 1) uniform UBO 
+{
+	mat4 projection;
+	mat4 model;
+	float tessAlpha;
+} ubo; 
+
+layout (location = 0) in vec3 inNormal[];
+layout (location = 1) in vec2 inUV[];
+
+layout (location = 0) out vec3 outNormal;
+layout (location = 1) out vec2 outUV;
+
+void main(void)
+{
+    gl_Position = (gl_TessCoord.x * gl_in[0].gl_Position) +
+                  (gl_TessCoord.y * gl_in[1].gl_Position) +
+                  (gl_TessCoord.z * gl_in[2].gl_Position);
+	gl_Position = ubo.projection * ubo.model * gl_Position;
+	
+	outNormal = gl_TessCoord.x*inNormal[0] + gl_TessCoord.y*inNormal[1] + gl_TessCoord.z*inNormal[2];
+	outUV = gl_TessCoord.x*inUV[0] + gl_TessCoord.y*inUV[1] + gl_TessCoord.z*inUV[2];
+}