#136 incomplete generated code

[Ben Litchfield]

Submitted by dieter von holten on old JIRA site.

http://jira.codehaus.org/browse/MIDDLEGEN-21

from looking at sample-code (ReservationPK.java) -
which may be outdated - it seems that the generated
code should be corrected:
setting the fields reservationId ... flightIdPK influences
the calculation of the hashCode. The StringBuffer used
for toString() is not so lucky: it keeps the value set on
the first call and is not affected by later changes of
the ...-fields.
Enhancement: the generated code should include a
timestamp when it was generated.