The selectSubnet() function offers two ways to find a subnet for a
particular interface: using the name of the interface that the subnet is
configured for; and using the packet source address. Also, the redundant
warning is removed if suitable subnet was not found as this warning is
already issued elsewhere.

Explicit allocation failures cause the return of packet to the client
indicating that the address allocation has been refused.  Also added
was a "catch" for other exceptions - this causes the packet from the
client that generated the exception to be ignored.

Also correct error messages in the configuration parser: the
same error is logged on any parser error, both creation and
running.  The text was made more general.

 - DORA support added
 - REQUEST/Renewing support added
 - RELEASE support added
 - AllocationEngine now supports lease4 renewals
 - many other smaller code additions
 - many tests written

This is from Tomek in private email.

misspellings or typos

spelled out "wg" so next spell check doesn't fail on it

periods at end of sentences (even for incomplete bullet items
to be consistent)

remove double words (the the, up up)

This was not reviewed, but is mostly minor changes.
Two items I was unclear about I confirmed on jabber.

using tools/reorder_message_file.py to reorder

- tests use automatic variables now for Dhcpv6Srv
- comments clarified
- extra log messages added

The message when the DHCPv6 database backend is started now includes
both the type and the name of the database.