Examples - use idiomatic paren placing

Author: samaaron

etc/examples/illusionist/chord_inversions.rb

@@ -4,8 +4,8 @@
 # https://twitter.com/wpgFactoid/status/666692596605976576
 
 [1, 3, 6, 4].each do |d|
-  range(-3,3).each do |i|
-    play_chord chord_degree d, :c, :major, 3, invert: i
+  (range -3, 3).each do |i|
+    play_chord (chord_degree d, :c, :major, 3, invert: i)
     sleep 0.25
   end
 end