Fix tidy issues

Author: GuillaumeGomez

src/librustc_error_codes/error_codes/E0015.md

@@ -1,4 +1,5 @@
-A constant item was initialized with something that is not a constant expression.
+A constant item was initialized with something that is not a constant
+expression.
 
 Erroneous code example:
 

src/librustc_error_codes/error_codes/E0107.md

@@ -25,4 +25,3 @@ fn main() {
                     //        expected 0, found 1
 }
 ```
-

src/librustc_error_codes/error_codes/E0369.md

@@ -26,4 +26,3 @@ left and may require reallocation. This requires ownership of the string
 on the left. If something should be added to a string literal, move the
 literal to the heap by allocating it with `to_owned()` like in
 `"Your text".to_owned()`.
-

src/librustc_error_codes/error_codes/E0404.md

@@ -41,4 +41,3 @@ trait Foo {
 
 fn bar<T: Foo>(t: T) {} // ok!
 ```
-

src/librustc_error_codes/error_codes/E0458.md

@@ -10,4 +10,3 @@ Please specify a valid "kind" value, from one of the following:
 * static
 * dylib
 * framework
-

src/librustc_error_codes/error_codes/E0633.md

@@ -21,4 +21,3 @@ The `#[unwind]` attribute should be used as follows:
 
 NB. The default behavior here is "allowed", but this is unspecified
 and likely to change in the future.
-

src/librustc_error_codes/error_codes/E0635.md

@@ -5,4 +5,3 @@ Erroneous code example:
 ```compile_fail,E0635
 #![feature(nonexistent_rust_feature)] // error: unknown feature
 ```
-

src/librustc_error_codes/error_codes/E0636.md

@@ -7,4 +7,3 @@ Erroneous code example:
 #![feature(rust1)]
 #![feature(rust1)] // error: the feature `rust1` has already been declared
 ```
-

src/librustc_error_codes/error_codes/E0641.md

@@ -16,4 +16,4 @@ let a = &(String::from("Hello world!")) as *const _; // Ok
 let b = 0 as *const i32; // Ok
 
 let c: *const i32 = 0 as *const _; // Ok
-```
+```

src/librustc_error_codes/error_codes/E0644.md

@@ -27,4 +27,3 @@ closure call itself by capturing a `&Fn()` object or `fn()` pointer
 that refers to itself. That is permitting, since the closure would be
 invoking itself via a virtual call, and hence does not directly
 reference its own *type*.
-