Add rust.target_dir config option

Author: Xanewok

package.json

@@ -284,7 +284,15 @@
                     ],
                     "default": null,
                     "description": "Number of Cargo jobs to be run in parallel."
-                }
+                },
+                "rust.target_dir": {
+                    "type": [
+                        "string",
+                        "null"
+                    ],
+                    "default": null,
+                    "description": "When specified, it places the generated analysis files at the specified target directory. By default it is placed target/rls directory."
+                },
             }
         }
     }