Added planet atmosphere shader

core/assets/shaders/atmosphere.vert

@@ -0,0 +1,13 @@
+attribute vec4 a_position;
+
+varying vec4 v_position;
+varying mat4 v_model;
+
+uniform mat4 u_model;
+uniform mat4 u_projection;
+
+void main(){
+    v_position = a_position;
+    v_model = u_model;
+    gl_Position = u_projection*u_model*a_position;
+}