Changes

tsk17 Adds functionalities to the team service
Adds findByNameDescription method that allows to find a team by name and
description. Adds findByAdmin method that allows to get a list of teams
managed by a given user. Adds findBySport method that allows to get a
list of teams of agiven sport. Adds create method to create a new team
in the database. Adds update method to update a team in the database. 
Adds delete method to logical delete a team in the database. Updates the
TeamDataset class. Updates the XML datasets for testing. Adds a SQL
script for testing.