Use access time in some selectors

For now, only persons, instruments and ensembles will be ordered by
access time.

database/src/ensembles.rs

@@ -64,4 +64,13 @@ impl Database {
         let ensembles = ensembles::table.load::<Ensemble>(&self.connection)?;
         Ok(ensembles)
     }
+
+    /// Get recently used ensembles.
+    pub fn get_recent_ensembles(&self) -> Result<Vec<Ensemble>> {
+        let ensembles = ensembles::table
+            .order(ensembles::last_used.desc())
+            .load::<Ensemble>(&self.connection)?;
+
+        Ok(ensembles)
+    }
 }

database/src/instruments.rs

@@ -67,4 +67,13 @@ impl Database {
 
         Ok(instruments)
     }
+
+    /// Get recently used instruments.
+    pub fn get_recent_instruments(&self) -> Result<Vec<Instrument>> {
+        let instruments = instruments::table
+            .order(instruments::last_used.desc())
+            .load::<Instrument>(&self.connection)?;
+
+        Ok(instruments)
+    }
 }

database/src/persons.rs

@@ -77,4 +77,13 @@ impl Database {
 
         Ok(persons)
     }
+
+    /// Get recently used persons.
+    pub fn get_recent_persons(&self) -> Result<Vec<Person>> {
+        let persons = persons::table
+            .order(persons::last_used.desc())
+            .load::<Person>(&self.connection)?;
+
+        Ok(persons)
+    }
 }