#336 Simplify coding of list pattern data object using annotation

[Miro Halas]

When implementing list pattern in data objects, the task to perform are
- add numeric constant for each attribute
- add object representation of numeric constant for certail attributes
- add array usually called ALL_COLUMNS with all the numeric constant
- add array usually called DEFAULT_LIST_COLUMNS with the numeric constants for columsn that should be loaded for list
- add constants for sort columns and sort orders of the list columns

Consider using annotation for attributes (in similar style as XDoclet is doing) to outline what attributes are retrievable from the database, which are listable, which are used for sorting, etc. It might be easier to add annotations than to code all these constants. On the other hand, how does it impact the searchability and maintenability of the code.