-Have setup the xml parser to read mail and parcels, and to read them
with conditions. (Filter them). 
-Comparators and XMLReader class no longer needed, so they are banished. 
-mailevents.xml is what it is.
-Have made some comparators in Mail, these are used by
Collections.sort() to sort the mail in various ways within the array
list.
-Have added constructors to Mail and parser and getter setters so that
they can accept priority as int or string
To Come:
-function to add data to an xml file.
-Function calls to return specific data types.
tl
Added method to add new mail events to xml by passing XMLWorker an
object.
Keeping the XMLWorker up to date
Hopefully this commit solves my issues, and doesn't cause any for anyone
else.