Update to drupal 8.0.0-rc1. For more information, see https://www.drupal.org/node/2582663

core/modules/comment/config/install/core.entity_view_mode.comment.full.yml

@@ -1,8 +1,9 @@
-id: comment.full
-label: 'Full comment'
+langcode: en
 status: false
-cache: true
-targetEntityType: comment
 dependencies:
   module:
     - comment
+id: comment.full
+label: 'Full comment'
+targetEntityType: comment
+cache: true

core/modules/comment/config/install/field.storage.comment.comment_body.yml

@@ -15,3 +15,4 @@ cardinality: 1
 translatable: true
 indexes: {  }
 persist_with_no_fields: true
+custom_storage: false

core/modules/comment/config/install/system.action.comment_publish_action.yml

@@ -1,9 +1,10 @@
-id: comment_publish_action
-label: 'Publish comment'
-status: true
 langcode: en
-type: comment
-plugin: comment_publish_action
+status: true
 dependencies:
   module:
     - comment
+id: comment_publish_action
+label: 'Publish comment'
+type: comment
+plugin: comment_publish_action
+configuration: {  }

core/modules/comment/config/install/system.action.comment_save_action.yml

@@ -1,9 +1,10 @@
-id: comment_save_action
-label: 'Save comment'
-status: true
 langcode: en
-type: comment
-plugin: comment_save_action
+status: true
 dependencies:
   module:
     - comment
+id: comment_save_action
+label: 'Save comment'
+type: comment
+plugin: comment_save_action
+configuration: {  }

core/modules/comment/config/install/system.action.comment_unpublish_action.yml

@@ -1,9 +1,10 @@
-id: comment_unpublish_action
-label: 'Unpublish comment'
-status: true
 langcode: en
-type: comment
-plugin: comment_unpublish_action
+status: true
 dependencies:
   module:
     - comment
+id: comment_unpublish_action
+label: 'Unpublish comment'
+type: comment
+plugin: comment_unpublish_action
+configuration: {  }