graph2: Added Story mutations

graph2/schema/types/Story.gql

@@ -112,6 +112,9 @@ input StoryEditInput {
 
   # Set the fictional date of the story.
   fictionalDate: Date
+
+  # Clear the fictional date of the story.
+  clearFictionalDate: Boolean
 }
 
 # Input for the addStoryTag mutation
@@ -132,6 +135,12 @@ input StoryTagRemoveInput {
   tag: TagInput!
 }
 
+# Input for the removeStory mutation
+input StoryRemoveInput {
+  # What story to remove.
+  id: String!
+}
+
 # Possible values for Story.category
 enum StoryCategory {
   # General information