Fix group and ID for typdef items

This patch fixes the group and ID stored in the ItemType enum for the
ItemType::Typedef variant so that typedefs show up in the module
summary.

CHANGELOG.md

@@ -13,6 +13,7 @@ SPDX-License-Identifier: MIT
   - Fix the definition of methods to only contain the actual definition.
   - Remove spurious members in module documentation.
   - Show the definition for constants and typedefs.
+  - Fix group and ID for typdef items.
 
 ## v0.1.2 (2020-07-25)
 

src/doc.rs

@@ -259,7 +259,7 @@ impl ItemType {
             ItemType::Struct => "struct",
             ItemType::Enum => "enum",
             ItemType::Function => "function",
-            ItemType::Typedef => "typedef",
+            ItemType::Typedef => "type",
             ItemType::Static => "static",
             ItemType::Trait => "trait",
             ItemType::Impl => "impl",
@@ -321,7 +321,7 @@ impl ItemType {
             ItemType::Struct => "structs",
             ItemType::Enum => "enums",
             ItemType::Function => "functions",
-            ItemType::Typedef => "typedefs",
+            ItemType::Typedef => "types",
             ItemType::Static => "statics",
             ItemType::Trait => "traits",
             ItemType::Impl => "impls",