Auto merge of #43130 - GuillaumeGomez:rustdoc-fn-spacing, r=QuietMisdreavus

Add spacing between trait functions

Fixes #42988.

<img width="1440" alt="screen shot 2017-07-09 at 17 02 16" src="https://user-images.githubusercontent.com/3050060/27995068-672a3208-64c8-11e7-9bc7-c7288f2cd27b.png">

src/librustdoc/html/render.rs

@@ -2087,15 +2087,19 @@ fn item_trait(w: &mut fmt::Formatter, cx: &Context, it: &clean::Item,
         if !consts.is_empty() && !required.is_empty() {
             w.write_str("\n")?;
         }
-        for m in &required {
+        for (pos, m) in required.iter().enumerate() {
             write!(w, "    ")?;
             render_assoc_item(w, m, AssocItemLink::Anchor(None), ItemType::Trait)?;
             write!(w, ";\n")?;
+
+            if pos < required.len() - 1 {
+               write!(w, "<div class='item-spacer'></div>")?;
+            }
         }
         if !required.is_empty() && !provided.is_empty() {
             w.write_str("\n")?;
         }
-        for m in &provided {
+        for (pos, m) in provided.iter().enumerate() {
             write!(w, "    ")?;
             render_assoc_item(w, m, AssocItemLink::Anchor(None), ItemType::Trait)?;
             match m.inner {
@@ -2106,6 +2110,9 @@ fn item_trait(w: &mut fmt::Formatter, cx: &Context, it: &clean::Item,
                     write!(w, " {{ ... }}\n")?;
                 },
             }
+            if pos < provided.len() - 1 {
+               write!(w, "<div class='item-spacer'></div>")?;
+            }
         }
         write!(w, "}}")?;
     }

src/librustdoc/html/static/rustdoc.css

@@ -658,6 +658,11 @@ h3 > .collapse-toggle, h4 > .collapse-toggle {
 	padding-left: 10px;
 }
 
+.item-spacer {
+	width: 100%;
+	height: 12px;
+}
+
 span.since {
 	position: initial;
 	font-size: 20px;