Add a warning when not running in december

src/day02.rs

@@ -9,7 +9,7 @@ enum Instruction {
 }
 
 impl Day for Day02 {
-    fn init(content: String) -> Self where Self: Sized {
+    fn init(content: String) -> Self {
         let lines = content.split("\n").map(str_to_instr).collect::<Vec<Instruction>>();
         Day02(lines)
     }

src/main.rs

@@ -57,7 +57,10 @@ fn main() {
             run_day(&days, v as usize);
         }
     } else {
-        let v = chrono::Local::now().day();
+        let v = chrono::Local::now();
-        run_day(&days, v as usize)
+        if v.month() != 12 {
+            println!("This was really only meant to be used in december...")
+        }
+        run_day(&days, v.day() as usize)
     }
 }