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THIS PROBLEM WAS TAKEN FROM THE FINALS OF THE TOPCODER INVITATIONAL TOURNAMENT

PROBLEM STATEMENT
To fulfill one of the many demands of its members, a certain company organizing
programming competitions must implement a routine to sort users in a list by
several options.  The users can be sorted by handle, rating, or log in time.
Each of the options can be sorted forwards or backwards.  

Implement a class UserListSorter that contains a method sortUsersBy.  The
method takes as its parameters a String[] and two integer sort parameters.  The
method returns a String[] that contains the handles of the users after it sorts
the given input String[] based on the specified sort parameters.

DEFINITION
Class Name: UserListSorter
Method Name: sortUsersBy
Parameters: String[], int, int
Returns: String[]
Method signature (be sure your method is public):  String[] sortUsersBy
(String[] userInfo, int sortBy, int order); 

TopCoder will ensure the validity of the inputs.  Inputs are valid if all of
the following criteria are met:
- userInfo contains between 1 and 50 elements, inclusive.
- The elements of userInfo are in the form "HANDLE RATING LOGINTIME". 
* HANDLE is unique and contains between 1 and 20 (inclusive) lowercase
letters (a-z).
   * RATING is an integer between 0 and 3000, inclusive.
* LOGINTIME is a String of the form hh:mm where hh is between 00 and 23,
inclusive, and mm is between 00 and 59, inclusive.
- sortBy is an int representing how the list should be sorted.  Valid values of
sortBy are:
  1 for sort by handle
  2 for sort by rating
  3 for sort by login time
- order will be an int that is 1 for sort forwards and 0 for sort backwards.

NOTES
- Sort Definitions:
  * Sort by handle forwards puts the handles in alphabetical order.
  * Sort by handle backwards puts the handles in reverse alphabetical order.
  * Sort by rating forwards puts the ratings in increasing order.
  * Sort by rating backwards puts the ratings in decreasing order.
* Sort by login time forwards puts the login times in sequential order
(earliest time at top of list).
* Sort by login time backwards puts the login times in reverse sequential
order.
* If in a sort, multiple people have identical sort by values, their relative
order in the output should be the same as their relative order in the input.
- All letters of HANDLES are lowercase.

EXAMPLES
For the examples, users=
{
 "aaa 1500 10:30",
 "a 728 10:30",
 "aa 2898 14:32",
}

if sortBy=1 and order=1, the user names are put in alphabetical order, and the
method returns:
{
 "a",
 "aa",
 "aaa"
}

For the examples, users=
{
 "dwarfsleepy 728 10:30",
 "mitalub 2898 14:32",
 "ads 1500 10:30",
 "mike 1727 22:00",
 "romana 1200 09:00",
 "td 1299 01:00",
 "dok 1200 17:25",
 "chuck 1200 18:00"
}

if sortBy=1 and order=1, the user names are put in alphabetical order, and the
method returns:
{
 "ads",
 "chuck",
 "dok",
 "dwarfsleepy",
 "mike",
 "mitalub",
 "romana",
 "td"
}

if sortBy=1 and order=0, the user names are put in reverse alphabetical order,
and the method returns:
{
 "td",
 "romana",
 "mitalub",
 "mike",
 "dwarfsleepy",
 "dok",
 "chuck",
 "ads"
}

if sortBy=2 and order=1, the users should be put in order of increasing rating,
and the method returns:
{
 "dwarfsleepy",
 "romana",
 "dok",
 "chuck",
 "td",
 "ads",
 "mike",
 "mitalub"
}

if sortBy=2 and order=0, the users should be put in order of decreasing rating,
and the method returns:
{
 "mitalub",
 "mike",
 "ads",
 "td",
 "romana",
 "dok",
 "chuck",
 "dwarfsleepy"
}

if sortBy=3 and order=1, the users should be put in the sequential order they
logged in, and the method returns:
{
 "td",
 "romana",
 "dwarfsleepy",
 "ads",
 "mitalub",
 "dok",
 "chuck",
 "mike"
}

if sortBy=3 and order=0, the users should be put in the reverse sequential
order of their logins, and the method returns:
{
 "mike",
 "chuck",
 "dok",
 "mitalub",
 "dwarfsleepy",
 "ads",
 "romana",
 "td"
}