Add button to remove a tag

CHDataManagement/Model/Content.swift

@@ -145,6 +145,17 @@ final class Content: ObservableObject {
         // TODO: Check for page links and other references in content
     }
 
+    func remove(_ tag: Tag) {
+        tags.remove(tag)
+        for post in posts {
+            post.tags.remove(tag)
+        }
+        for page in pages {
+            page.tags.remove(tag)
+        }
+        // TODO: Check for tag links and other references is content
+    }
+
     // MARK: Loading
 
     func file(withOutputPath: String) -> FileResource? {