Add yet-another-react-lightbox package and update .gitignore to exclude node_modules

frontend/node_modules/js-yaml/lib/common.js

@@ -1,59 +0,0 @@
-'use strict';
-
-
-function isNothing(subject) {
-  return (typeof subject === 'undefined') || (subject === null);
-}
-
-
-function isObject(subject) {
-  return (typeof subject === 'object') && (subject !== null);
-}
-
-
-function toArray(sequence) {
-  if (Array.isArray(sequence)) return sequence;
-  else if (isNothing(sequence)) return [];
-
-  return [ sequence ];
-}
-
-
-function extend(target, source) {
-  var index, length, key, sourceKeys;
-
-  if (source) {
-    sourceKeys = Object.keys(source);
-
-    for (index = 0, length = sourceKeys.length; index < length; index += 1) {
-      key = sourceKeys[index];
-      target[key] = source[key];
-    }
-  }
-
-  return target;
-}
-
-
-function repeat(string, count) {
-  var result = '', cycle;
-
-  for (cycle = 0; cycle < count; cycle += 1) {
-    result += string;
-  }
-
-  return result;
-}
-
-
-function isNegativeZero(number) {
-  return (number === 0) && (Number.NEGATIVE_INFINITY === 1 / number);
-}
-
-
-module.exports.isNothing      = isNothing;
-module.exports.isObject       = isObject;
-module.exports.toArray        = toArray;
-module.exports.repeat         = repeat;
-module.exports.isNegativeZero = isNegativeZero;
-module.exports.extend         = extend;