Standardize resource use #34
Description
Resources (such as images, dtd & html files) are gathered and used very liberally in the application, making it very difficult to determine which resources are actually used, and where.
It would be incalculably better to abstract away resource fetching and usage, and their paths as well.
This could also aid future testing, since this "ResourceManager" concept could be mocked.
Furthermore, once this concept is introduced and used the application, moving resources to the standard folder will become trivially easy. (See #7)