core: Reformat the crate docs to look nicer

Author: brson

src/libcore/core.rc

@@ -9,20 +9,20 @@
 
 #[doc(
     brief = "The Rust core library",
-    desc =
-    "The core library provides functionality that is closely tied to \
-     the Rust built-in types and runtime services, or that is used in nearly \
-     every non-trivial program.\
-     \n\n\
-     The core library is linked by default to all crates and the contents \
-     imported. The effect is as though the user had written the following: \
-     \n\n\
-     ~~~\n\
-     use core; \n\
-     import core::*;\n\
-     ~~~\n\
-     \n\
-     This behavior can be disabled with the `--no-core` compiler flag."
+    desc = "
+The core library provides functionality that is closely tied to
+the Rust built-in types and runtime services, or that is used in nearly
+every non-trivial program.
+
+The core library is linked by default to all crates and the contents
+imported. The effect is as though the user had written the following:
+
+~~~
+use core;
+import core::*;
+~~~
+
+This behavior can be disabled with the `--no-core` compiler flag."
 )];
 
 export box, char, float, bessel, f32, f64, int, str, ptr;