add residue writer, Arithmetic Coding commented
add decoding process in Encoder.java, add psnr calculation
add decoder, move some of the java files from Package encoder to Package common, add xml parser, add xml file.
add inversePsvd, change diag arithmetic coding with DataOutputStream, add psnr.xml
add psvdTest, add xmlDocument to create xml and parse xml, add dirMaker to make folders, add process redirection, add common folder to make psvdTest work
add srcPath into PsvdTest