add type defenitions

types/lib/Placeholder.d.ts

@@ -0,0 +1,17 @@
+import * as React from 'react';
+import { CSSModule } from './index';
+
+export interface PlaceholderProps extends React.HTMLAttributes<HTMLElement> {
+  [key: string]: any;
+  color?: string;
+  tag?: React.ElementType;
+  animation?: string;
+  className?: string;
+  cssModule?: CSSModule;
+  size?: string;
+  widths?: string[];
+  innerRef?: React.Ref<HTMLElement>;
+}
+
+declare class Placeholder extends React.Component<PlaceholderProps> {}
+export default Placeholder;

types/lib/PlaceholderButton.d.ts

@@ -0,0 +1,14 @@
+import * as React from 'react';
+import { CSSModule } from './index';
+
+export interface PlaceholderButtonProps extends React.HTMLAttributes<HTMLElement> {
+  [key: string]: any;
+  size?: string;
+  color?: string;
+  outline?: boolean;
+  cssModule?: CSSModule;
+  tag?: React.ElementType;
+}
+
+declare class PlaceholderButton extends React.Component<PlaceholderButtonProps> {}
+export default PlaceholderButton;