Rollup merge of rust-lang#54368 - GuillaumeGomez:reduce-side-padding,…

… r=QuietMisdreavus

Reduce code block sides padding

Fixes rust-lang#42013.

<img width="1440" alt="screen shot 2018-09-19 at 22 58 32" src="https://user-images.githubusercontent.com/3050060/45781266-c6525680-bc5f-11e8-8eb0-98fc4c22a96e.png">

r? @QuietMisdreavus

src/librustdoc/html/static/rustdoc.css

@@ -139,7 +139,7 @@ code, pre {
 }
 .docblock code, .docblock-short code {
 	border-radius: 3px;
-	padding: 0 0.2em;
+	padding: 0 0.1em;
 }
 .docblock pre code, .docblock-short pre code, .docblock code.spotlight {
 	padding: 0;