make Element struct implement Copy and Clone trait

src/element.rs

@@ -1,5 +1,5 @@
 /// Contains the information of a single element
-#[derive(Debug)]
+#[derive(Debug, Copy, Clone)]
 pub struct Element {
     pub atomic_number: u32,
     pub atomic_group: Option<u32>,
@@ -25,20 +25,20 @@ pub struct Element {
 }
 
 /// The three possible states
-#[derive(Debug)]
+#[derive(Debug, Copy, Clone)]
 pub enum State {
     Solid,
     Liquid,
     Gas,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Copy, Clone)]
 pub struct IonRadius {
     pub radius: f32,
     pub variation: &'static str,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Copy, Clone)]
 pub enum Year {
     Ancient,
     Known(u16),