Add today helper method to YearMonth

src/shared_api_lib/src/year_month.rs

@@ -1,3 +1,5 @@
+use chrono::Datelike;
+
 #[derive(Copy, Clone)]
 pub struct YearMonth {
     pub year: i32,
@@ -39,6 +41,14 @@ impl YearMonth {
             _ => None,
         }
     }
+
+    pub fn today() -> YearMonth {
+        let now = chrono::prelude::Local::now();
+        return YearMonth {
+            year: now.year(),
+            month: u8::try_from(now.month()).unwrap(),
+        };
+    }
 }
 
 impl std::fmt::Display for YearMonth {