Use/fix ron code blocks (#541)

README.md

@@ -16,7 +16,7 @@ structs, enums, tuples, arrays, generic maps, and primitive values.
 
 ## Example
 
-```rust,ignore
+```ron
 GameConfig( // optional struct name
     window_size: (800, 600),
     window_title: "PAC-MAN",
@@ -98,7 +98,7 @@ There also is a very basic, work in progress specification available on
 
 ### Same example in RON
 
-```rust,ignore
+```ron
 Scene( // class name is optional
     materials: { // this is a map
         "metal": (

docs/extensions.md

@@ -21,15 +21,15 @@ struct Object {
 
 Without `unwrap_newtypes`, because the value `5` can not be saved into `NewType(u32)`, your RON document would look like this:
 
-``` ron
+```ron
 (
     new_type: (5),
 )
 ```
 
 With the `unwrap_newtypes` extension, this coercion is done automatically. So `5` will be interpreted as `(5)`.
 
-``` ron
+```ron
 #![enable(unwrap_newtypes)]
 (
     new_type: 5,
@@ -98,15 +98,15 @@ pub enum Enum {
 
 Without `unwrap_variant_newtypes`, your RON document would look like this:
 
-``` ron
+```ron
 (
     variant: A(Inner(a: 4, b: true)),
 )
 ```
 
 With the `unwrap_variant_newtypes` extension, the first structural layer inside a newtype variant will be unwrapped automatically:
 
-``` ron
+```ron
 #![enable(unwrap_newtypes)]
 (
     variant: A(a: 4, b: true),