Fix the tour's example for empty array & dictionary syntax (#56)

These examples used to contrast the literal [] and initializer [String]()
syntax, but we revised the book to remove the latter as part of a style update.

639bcc6

Fixes rdar://101867425

Author: amartini51

Sources/TSPL/TSPL.docc/GuidedTour/GuidedTour.md

@@ -263,6 +263,10 @@ occupations["Jayne"] = "Public Relations"
   ```
 -->
 
+<!--
+  iBooks Store screenshot begins here.
+-->
+
 Arrays automatically grow as you add elements.
 
 ```swift
@@ -280,44 +284,43 @@ print(fruits)
   ```
 -->
 
-To create an empty array or dictionary,
-use the initializer syntax.
+You also use brackets to write an empty array or dictionary.
+For an array, write `[]`,
+and for a dictionary, write `[:]`.
 
 ```swift
-let emptyArray: [String] = []
-let emptyDictionary: [String: Float] = [:]
+fruits = []
+occupations = [:]
 ```
 
 <!--
   - test: `guided-tour`
   
   ```swifttest
-  -> let emptyArray: [String] = []
-  -> let emptyDictionary: [String: Float] = [:]
+  -> fruits = []
+  -> occupations = [:]
   ```
 -->
 
-If type information can be inferred,
-you can write an empty array as `[]`
-and an empty dictionary as `[:]` ---
-for example, when you set a new value for a variable
-or pass an argument to a function.
-
-<!--
-  iBooks Store screenshot begins here.
--->
+If you're assigning an empty array or dictionary to a new variable,
+or another place where there isn't any type information,
+you need to specify the type.
 
 ```swift
-fruits = []
-occupations = [:]
+let emptyArray: [String] = []
+let emptyDictionary: [String: Float] = [:]
 ```
 
+
 <!--
   - test: `guided-tour`
   
   ```swifttest
-  -> fruits = []
-  -> occupations = [:]
+  -> let emptyArray: [String] = []
+  -> let emptyDictionary: [String: Float] = [:]
+  ---
+  -> let anotherEmptyArray = [String]()
+  -> let emptyDictionary = [String: Float]()
   ```
 -->