Added a first draft of a filter feature to the app. For now it only has two possible filter entries: One for the location of the freezer, one for the type of entry.

The biggest challenges where how to send the request to express.js (needed to add a parameter to the URL) and reseting the form to its default state. Though I wonder why this keeps being so complicated?

Adding more will be done after I took care of the pagination, I think.