allow override containerStyle (#16)

* allow override containerStyle

* revert formatting

* add prepare script so unpublished module can install

* remove trailing comma package.json

* fix up lint and prepare script

package.json

@@ -8,7 +8,8 @@
     "dev": "webpack-dev-server",
     "pretest": "rimraf dist && tslint --project . && tsc -p .",
     "test": "jest --config=jestconfig.json",
-    "prepublish": "npm test"
+    "prepublish": "npm test",
+    "prepare": "rimraf dist && tsc -p ."
   },
   "repository": {
     "type": "git",

src/components/PullToRefresh.tsx

@@ -9,6 +9,7 @@ export interface PullToRefreshProps {
     onRefresh: () => Promise<any>;
     triggerHeight?: number | "auto";
     backgroundColor?: string;
+    containerStyle?: React.CSSProperties;
     startInvisible?: boolean;
 }
 
@@ -206,6 +207,12 @@ export class PullToRefresh extends React.Component<PullToRefreshProps, PullToRef
             zIndex: 1,
         };
 
+        if (this.props.containerStyle) {
+          Object.keys(this.props.containerStyle).forEach((key: string) => {
+            containerStyle[key] = this.props.containerStyle[key];
+          });
+        }
+
         if (backgroundColor) {
             containerStyle.backgroundColor = backgroundColor;
         }