Release Name: 0.5.0

Notes:
This is the new development release. It has lots of one-line convenience
methods for defining fields in domain classes and overriding methods like
tableName and sqlPrimaryKeyName


Changes:
* ObjectStore raises an informative error if a domain class' primary key is
  defined incorrectly
* instead of using an external config file, you can set LafcadioConfig's
  values using LafcadioConfig.setValues
* convenience methods for defining domain class methods in Ruby
* fixed bug on ObjectStore#getClients( 1, 'client_id' ) for domain classes
  with non-standard primary keys
* one-line methods for overriding DomainObject.tableName and
  DomainObject.sqlPrimaryKeyName
* lots of code cleanup
* WARNING: Removed DecimalField#precision; ObjectField#defaultFieldName,
  #hideLabel, #writeOnce, #hideDisplay, #default, #notUniqueMsg;
  LinkField#listener, #newDuringEdit, #sortField; PasswordField#maxLength,
  #autoGenerate; TextField#large, #size; HashOfArrays