Auto merge of rust-lang#2131 - jtgeibel:clippy/iter-nth-zero, r=jtgeibel

Fix a new lint - clippy::iter-nth-zero

This lint was recently added to nightly and is a reasonable change.

I plan to r+ soon, so:
r? @ghost

Author: bors

src/models/krate.rs

@@ -252,7 +252,7 @@ impl Crate {
         Self::valid_feature_name(name)
             && name
                 .chars()
-                .nth(0)
+                .next()
                 .map(char::is_alphabetic)
                 .unwrap_or(false)
     }