* refactor: Add DarkTheme, new colors in theme & update components to use it
* chore: Remove 'console.log' statements
* chore: Change dark theme property from string to boolean
* feat: Add ability to toggle the theme from the drawer
* fix: Wrap typography example screen with 'withTheme'
* style: Update components to use correct dark theme colors
* style: Update dark theme primary color and rn-navigation toolbar now gets the color from the theme
* style: Add color prop to DrawerItem and update the example
* style: Change the unchecked color in both Checkbox and RadioButton
* chore: Add `yarn-error.log` to `.gitignore`
* chore: Use lodash instead of lodash.merge
* chore: Address PR comments
