Fix the function names in calls of the 2.3 section in docs/gettingstarted.md.

docs/gettingstarted.md

@@ -55,9 +55,9 @@ If a function does have parameters, you can call it with arguments in the right
 addNumbers(int a, int b, int c, int d) >> {
   println(a + b + c + d)
 }
-helloWorld(1, 2, 3, 4) # Call without names
-helloWorld(a = 1, b = 2, c = 3, d = 4) # Call with names
-helloWorld(1, c = 3, b = 2, d = 4)
+addNumbers(1, 2, 3, 4) # Call without names
+addNumbers(a = 1, b = 2, c = 3, d = 4) # Call with names
+addNumbers(1, c = 3, b = 2, d = 4)
 ```
 
 Note that println is the only function that will get transpiled to its equivalent.