readme: recommend regex = 1

BurntSushi · web-flow · commit 607ac5c48cb6 · 2018-06-29T10:55:27.000-04:00
PR #494
diff --git a/README.md b/README.md
@@ -29,7 +29,7 @@ Add this to your `Cargo.toml`:
 
 ```toml
 [dependencies]
-regex = "1.0.0"
+regex = "1"
 ```
 
 and this to your crate root:
