Add discoverSystemIncludes option

Author: rianneogi

package.json

@@ -740,6 +740,11 @@
           "default": true,
           "description": "If true, cquery will highlight inactive regions."
         },
+        "cquery.misc.discoverSystemIncludes": {
+          "type": "boolean",
+          "default": true,
+          "description": "If true, cquery will detect system includes using clang -E."
+        },
         "cquery.completion.include.maximumPathLength": {
           "type": "integer",
           "default": 37,