Sc204/alg in output

The algorithm used is now mentioned in the output file names. Also, date and time are in there. Did not make a different branch for that, because that was a very small job.

umbra/controller.py

@@ -164,13 +164,15 @@ class Controller:
                 path = self._view.ask_save_location()
                 mistake_results = self._model.create_mistake_frame()
                 delay_results = self._model.create_delay_frame()
+                mistake_title = self._compose_csv_title('mistakes')
+                delay_title = self._compose_csv_title('delay')
                 self._view.update_message('saved')
                 self._filewriter.write_frame(path,
                                              mistake_results,
-                                             'mistakes.csv')
+                                             mistake_title)
                 self._filewriter.write_frame(path,
                                              delay_results,
-                                             'delay.csv')
+                                             delay_title)
                 self._view.update_message('saved')
             except PermissionError:
                 self._view.update_message('no_dir')
@@ -219,3 +221,17 @@ class Controller:
         self._model.remove_task('', all=True)
         self._model.analysed = False
         self._view.button_status('compare', 'normal')
+
+    def _compose_csv_title(self, file_name):
+        """Composes a title for a .csv file for the output of this
+        program.
+
+        Args:
+            file_name: String that will be the start of the file name
+        Returns:
+            title: String starting with file_name, then the algorithm
+            last used
+        """
+        algorithm = self._model.last_used_algorithm()
+        title = "{}_{}.csv".format(file_name, algorithm)
+        return title