Add #push to Array besides shovel operator

#push is commonly used imho and it is also used in other languages (e.g. Javascript).

ruby.html.markdown

@@ -173,6 +173,8 @@ array[1..3] #=> [2, 3, 4]
 
 # Add to an array like this
 array << 6 #=> [1, 2, 3, 4, 5, 6]
+# Or like this
+array.push(6) #=> [1, 2, 3, 4, 5, 6]
 
 # Check if an item exists in an array
 array.include?(1) #=> true