Merge pull request #2059 from akhi3030/master

Minor: remove an extraneous `.`

src/ch15-03-drop.md

@@ -58,7 +58,7 @@ an instance of your type goes out of scope. We’re printing some text here to
 demonstrate when Rust will call `drop`.
 
 In `main`, we create two instances of `CustomSmartPointer` and then print
-`CustomSmartPointers created.`. At the end of `main`, our instances of
+`CustomSmartPointers created`. At the end of `main`, our instances of
 `CustomSmartPointer` will go out of scope, and Rust will call the code we put
 in the `drop` method, printing our final message. Note that we didn’t need to
 call the `drop` method explicitly.