Update g.json

Add GitDiffHelper plugin

repository/g.json

@@ -216,6 +216,17 @@
 				}
 			]
 		},
+		{
+			"name": "GitDiffHelper",
+			"details": "https://github.com/Scopart/GitDiffHelper",
+			"labels": ["git", "diff"],
+			"releases": [
+				{
+					"sublime_text": "*",
+					"details": "https://github.com/Scopart/GitDiffHelper/tags"
+				}
+			]
+		},
 		{
 			"name": "Git Status Files",
 			"details": "https://github.com/mkraft/git-status-files",