Added a save command to overunder to save the pattern to a file

src/overunder.py

@@ -36,6 +36,7 @@ def eval(cmds):
     global text
     global line_number
     global last_index
+    global pattern
 
     for cmd in cmds:
         if cmd == []:
@@ -75,6 +76,11 @@ def eval(cmds):
             pattern = text[0:line_number + 1]
             print('\n'.join(pattern))
 
+        elif cmd[0] == 'save':
+            pattern_file = open('output/patternfile.txt', 'w')
+            pattern_file.write('\n'.join(pattern))
+            pattern_file.close()
+            print('Your pattern has been saved in the output folder.')
 
         elif cmd[0] == 'quit':
             print('Come back soon!')