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

frontend/node_modules/postcss/lib/at-rule.js

@@ -1,25 +0,0 @@
-'use strict'
-
-let Container = require('./container')
-
-class AtRule extends Container {
-  constructor(defaults) {
-    super(defaults)
-    this.type = 'atrule'
-  }
-
-  append(...children) {
-    if (!this.proxyOf.nodes) this.nodes = []
-    return super.append(...children)
-  }
-
-  prepend(...children) {
-    if (!this.proxyOf.nodes) this.nodes = []
-    return super.prepend(...children)
-  }
-}
-
-module.exports = AtRule
-AtRule.default = AtRule
-
-Container.registerAtRule(AtRule)