1.	Decrypt the message when unifying data.
2.	Change the unify data format a little bit to better fit our database.
I do not want to change the database.
3.	Add a lot of exception control to make it robust.
4.	Now unify data also will include user which are not in our study as a
dummy user.
5.	Save data into file format,”phoneNum_startDate_endDate” for each
person.