fix capitalization of Disease properties

[VladimirAlexiev]

A bunch of Disease props did not conform to the capitalization convention (camelCase). Fixing them is a nuisance, since it involves:

• Moving the ObjectProperty page
• Deleting the redirect (ObjectProperty page)
• Finding out all template mappings that use the prop an fixing them. See example: http://mappings.dbpedia.org/index.php?title=Mapping_el:Πληροφορίες_ασθένειας&diff=39156&oldid=20633

Still needs to be done for more templates.