Add language links to switch between English and Spanish (#842)

* Add language links to gov banner

- align banners to site logo
- create Language component and snapshot test
- add Language component to GovBanner
- update namespace for betaBanner scss.d.ts file

* Update snapshots for each page

* Componentizes the GovBanner

- add styles
- add unit test
- token most styles to USWDS

* Add language icon and update snapshots

* Make language link text smaller

* Update total height of BetaBanner

* Add languageLink to scss.d.ts file

* Add language links to mobile

- add isDesktop prop to Language component
- refactors header links to a simple array
- update snapshots

* Add href value to language links

- update snapshots

* merge other PRs and add spanish links

- merge PR 817
- merge PR 794
- add spanish links for footer
- add diffEnEs.js to detect differences between two json files
- adds esNoBrackets.json
- update intl README

* Add government banner in spanish

* Add spanish content for About and Explore page

client/src/components/Language/Language.tsx

@@ -0,0 +1,39 @@
+import React from 'react';
+import {IntlContextConsumer, changeLocale} from 'gatsby-plugin-intl';
+
+// @ts-ignore
+import languageIcon from '/node_modules/uswds/dist/img/usa-icons/language.svg';
+import * as styles from './Language.module.scss';
+
+const languageName = {
+  en: 'English',
+  es: 'Español',
+};
+
+interface ILanguageProps {
+  isDesktop: boolean
+}
+
+const Language = ({isDesktop}:ILanguageProps) => {
+  return (
+    <div className={isDesktop ? styles.languageContainer : styles.languageContainerMobile}>
+      <img className={styles.languageIcon} src={languageIcon} alt={'language icon for selecting language'}/>
+      <IntlContextConsumer>
+        {({languages, language: currentLocale}) =>
+          languages.map((language: React.Key | null | undefined) => (
+            <a
+              href="#"
+              className={styles.languageLink}
+              key={language}
+              onClick={() => changeLocale(language)}
+            >
+              {languageName[language]}
+            </a>
+          ))
+        }
+      </IntlContextConsumer>
+    </div>
+  );
+};
+
+export default Language;