Single xml solution - compatibility with skill-set and special-set

Mana-mantis: #506.
Bumped protocol version to 3

This is so that master and lpc2012 use the same protocol again,
where starting attributes are sent on character creation.
Hide attribute sliders on character creation when appropriate

When the minimum and maximum values of the attributes are equal, then
there is nothing for the player to customize and the sliders are not
shown.

At the same time the dialog has been fixed to resize properly to any
number of modifiable attributes.
Fixed network layer doing delayed actor deletion

The delayed actor deletion was meant to be used during the logic calls,
to avoid modifying the container while it is being iterated. The
deletions happening from the network layer are not done while iterating
the set of actors, so it can delete immediately.

This fixes an issue where an NPC would disappear when changing
appearance on tmwAthena, because this was implemented as a remove + add,
which broke due to the delayed deletion.

Mantis-issue: 507
Reviewed-by: Jared Adams