Added a RegisterFailedException class.
Cleaned up the way registration errors are handled.

* The use of booleans to note registration success and failures
  have been replaced with the use of exceptions. The exception
  RegisterFailedException was created to support this.

* The return type of the registerStudent() function has been
  changed from bool to void to support the change to using
  exceptions as well.

* RegisterServiceImpl.java:Line 34; Reminder to check with Navin
  the ideal way of handling this.

* TODO: The client does not differentiate between random server
  exceptions and exceptions caused by integrity constraint issues.
  Some code should be written to handle the two differently.
RegisterFailedException can be handled differently from other exceptions.

Modified the necessary classes to allow the client to handle RegisterFailedException
differently.

* RegisterFailedException extends Exception instead of RuntimeException and implements
  Serializable. This is required for the exception to be sent over RPC.
Merge pull request #3 from Ayrx/cleanup

Cleanup handling of registration errors.
In the process of adding in login functionality through Apache Shiro.

* Moved register.gwt.xml to resources/ folder.
* Modified pom.xml to include Shiro dependencies.
* Added LoginService/LoginServiceAsync
* Added LoginFailedException

NOTE: Login functionality is not working yet.
Added a LoginScreen class.
Working implementation of the login form.

Added in a form interface for logins. The EntryPoint for both the
registration and login forms will be the same. Changing between the
two will involve setting the correct Screen to the container. A few
changes have been made to support this.

* Renamed the RegisterPage class to ContentPage.
* Renamed the container id in register.html.

Login functionality will utilize the Apache Shiro framework for
authentication and jBCrypt for password hashing. As Shiro does
not have support for Bcrypt, I extended the CredentialsMatcher
interface to add support for Bcrypt.
Added verification functions for password, email and contact fields.
Merge pull request #5 from Ayrx/field-validators

Added verification functions for password, email and contact fields.
Merge pull request #6 from Ayrx/login

Login
PostgreSQL implemented
Changed Made
Merge pull request #7 from Geraldlim91/master

Changed database used from MySQL to PostgreSQL. Made modifications to the registration page and corresponding database fields to reflect the needed information.