PDFBOX-1975: Transferred the improved ImageIOUtils and its tests from the trunk, modified for the pre-refactoring API; modified the POM to get the two "wrong license" ImageWriter plugins (levigo and jai_imageio) for test only

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/branches/1.8@1584105 13f79535-47bb-0310-9956-ffa450edef68