Added the necessary code to hopefully allow the downloading of unknown images to the Data folder on the disk and read from there. This will allow for someone with a limited amount of space on their computer (i.e. me and my macbook air) to not have to download images that they are never using, they can simply load them onto a webserver they have ready access to and load them as they need them. Additionally for when working in an offline environment I have created a getDummyImage method which returns a grey ligh grey image with the words, unable to locate and the name of the map.
Added lazy loading of map images from remote server to local machine.
Merge pull request #6 from etothepii/feature/loadMapImagesFromServerAsNeeded

Feature/load map images from server as needed