Fixed the target placement and made dynamic

Fixed problems with target placement and the collision box in custom world files and the rqt_rover_gui.
Made the targets dynamic since fixing the placement issues increased simulation speed substantially so we don't need to use static targets anymore.

simulation/models/at0/model.sdf

@@ -1,11 +1,11 @@
 <?xml version='1.0'?>
 <sdf version='1.4'>
 	<model name="at0">
-		<static>true</static>
+		<static>false</static>
 		<link name='link'>
-			<pose>0 0 0.025 0 0 0</pose>
+			<pose>0 0 0.0 0.0 0 0</pose>
 			<inertial>
-				<mass>0.1</mass>
+				<mass>0.01</mass> <!-- Set the mass of the target to 10 grams -->>
 				<inertia>
 					<ixx>0.00004</ixx>
 					<ixy>0.0</ixy>
@@ -16,7 +16,7 @@
 				</inertia>
 			</inertial>
 			<visual name='visual'>
-			  <transparency>0.001</transparency>
+			  <transparency>0.1</transparency>
 				<geometry>
 					<box>
 						<size>0.05 0.05 0.05</size>
@@ -27,16 +27,11 @@
 						<uri>model://at0/materials/scripts</uri>
 						<uri>model://at0/materials/textures</uri>
 						<name>at0/Diffuse</name>
-						<ambient>255 255 255 1</ambient>
-						<diffuse>255 255 255 1</diffuse>
-						<specular>0.1 0.1 0.1 1</specular>
-						<emissive>0 0 0 0</emissive>
-
 					</script>
 				</material>
 			</visual>
 			<collision name ='collision'>
-				<pose>0 0 -0.0125 0 0 0</pose>
+				<pose>0 0 0 0 0 0</pose>
 				<geometry>
 					<box>
 						<size>0.05 0.05 0.05</size>