docs: fix typo in README (#735)

.github/CONTRIBUTING.md

@@ -27,7 +27,7 @@ You will need [Node.js](http://nodejs.org) at `v8.0.0+` and [Yarn](https://yarnp
 After cloning the repo, run:
 
 ```bash
-$ yarn install # or yarn
+$ yarn install # or npm
 ```
 
 ### Commonly used NPM scripts
@@ -91,4 +91,4 @@ There are some other scripts available in the `scripts` section of the `package.
   - **`src/types`**: contains extra typescript typings including OpenAPI doc typings
   - **`src/utils`**: utility functions
   - **`src/styled-components.ts`**: - reexprots styled-components with proper typescript annotations using theme
-  - **`src/theme.ts`**: - default theme (colors, fonts, etc) used by all the components
+  - **`src/theme.ts`**: - default theme (colors, fonts, etc) used by all the components