Uploading pictures done

Users can now upload picture with a description to the databse. There is a global hook to use to fetch users posts. This hook will be updated with delete function, add comment and so on. The create post will be avilible through the sidebar which gives a pop-up where the user can upload an image and write a text. The post is created in the database with a document which conatins the url to the image which is stored in the firebase storage, but it also contains the text, date and so on.