Add headers to files

Add default headers to all created files
Add properties settings to the application

Initial addition of the settings class for system properties.
Add customised settings to the application

Add further implementation to the Properties.Settings class.
Provides a stubbed SaveAll() and LoadAll() method.
Additional helper methods added.
Add ExtensionMethods class

ExtensionMethods static class used to extend existing classes.
Currently only extending XmlWriter classes to make writing XML files
easier.
Settings class updated to save version data.
Add Account and WriteXmlConfig classes

Add WriteXmlConfig abstract class from which, Account class is realised.
Account class added and used in the settings to save account details.
Add Bill class to the project

Adds the bill class, used to store information about bills acting on
an account.
Add DirectDebit class

Adds the Direct Debit class, used to store direct debit information
for an account.
Add Transaction class to the project

Adds the Transaction class to store transaction information between
accounts.
Add Withdrawal class to the project

Adds the Withdrawal class, used to track cash withdrawals from an
account.
Add BalanceTransfer class to project

Balance transfer class added to the project to handle balance transfers
from one account to another.
Also refactored some common code.
Rename WriteXmlConfig to ActionBasics

Renamed the WriteXmlConfig class to better suit its purpose.
The ActionBasics class will be used to used to store XML data, and
as a basic framework for all account interaction classes.