Auto merge of #1596 - camelid:fix-readme, r=RalfJung

Fix README

Add a paragraph break in the license section for clarity.

## Before

![image](https://user-images.githubusercontent.com/37223377/97042945-a5d3e500-1526-11eb-9c16-49f17f253e44.png)

## After

![image](https://user-images.githubusercontent.com/37223377/97042981-b2f0d400-1526-11eb-88c4-0db1119c2781.png)

Author: bors

README.md

@@ -406,10 +406,13 @@ Violations of [Stacked Borrows] found that are likely bugs (but Stacked Borrows
 ## License
 
 Licensed under either of
+
   * Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or
     http://www.apache.org/licenses/LICENSE-2.0)
   * MIT license ([LICENSE-MIT](LICENSE-MIT) or
-    http://opensource.org/licenses/MIT) at your option.
+    http://opensource.org/licenses/MIT)
+
+at your option.
 
 ### Contribution