Resolve ESLint warnings

Various tweaks to either resolve ESLint warnings or to allow behaviors
(such as allowing default exports of objects)

web/gui-v2/.eslintrc.js

@@ -0,0 +1,14 @@
+export default {
+  rules: {
+    "import/no-anonymous-default-export": ["error", {
+      "allowArray": false,
+      "allowArrowFunction": false,
+      "allowAnonymousClass": false,
+      "allowAnonymousFunction": false,
+      "allowCallExpression": false, // backward compatibility -> e.g. export default foo(bar)
+      "allowNew": false,
+      "allowLiteral": false,
+      "allowObject": true
+    }]
+  }
+}

web/gui-v2/src/components/HeaderSlider.jsx

@@ -34,10 +34,9 @@ const HeaderSlider = ({
   );
 
   // Debounce handler for propagating internal changes to the outside
-  const externalHandler = (newVal) => onChange(newVal);
   const handleExternalChange = useMemo(() => {
-    return debounce(externalHandler, 300);
-  }, []);
+    return debounce(onChange, 300);
+  }, [onChange]);
 
   // Trigger external state change
   useEffect(

web/gui-v2/src/pages/index.js

@@ -1,6 +1,5 @@
 import React from 'react';
 import { css } from '@emotion/react';
-import { DateTime } from 'luxon';
 import { graphql, useStaticQuery } from 'gatsby';
 
 import { AppWrapper, InfoCard, breakpoints } from '@eto/eto-ui-components';