add new AS and ASP supervisors as well as FSM for AS

This is part of a new process hierarchy for proper operation of a SG
(Signalling Gateway) with a number of AS, each containing multiple ASP,
the respective state management, fail-over, etc.

The AS supervisor starts the AS fsm and the ASP supervisor.

The ASP supervisor will be used to start and maintain ASP fsm's
(xua_asp_fsm), which in turn link into the respective M2UA/M3UA/SUA
behavior.

Those ASP fsm's will then be used by the processes that represent the
SCTP associations.
diff --git a/src/sg_asp_sup.erl b/src/sg_asp_sup.erl
new file mode 100644
index 0000000..3c9e5ac
--- /dev/null
+++ b/src/sg_asp_sup.erl
@@ -0,0 +1,48 @@
+% SIGTRAN SGW ASP supervisor
+
+% (C) 2012 by Harald Welte <laforge@gnumonks.org>
+%
+% All Rights Reserved
+%
+% This program is free software; you can redistribute it and/or modify
+% it under the terms of the GNU Affero General Public License as
+% published by the Free Software Foundation; either version 3 of the
+% License, or (at your option) any later version.
+%
+% This program is distributed in the hope that it will be useful,
+% but WITHOUT ANY WARRANTY; without even the implied warranty of
+% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+% GNU General Public License for more details.
+%
+% You should have received a copy of the GNU Affero General Public License
+% along with this program.  If not, see <http://www.gnu.org/licenses/>.
+%
+% Additional Permission under GNU AGPL version 3 section 7:
+%
+% If you modify this Program, or any covered work, by linking or
+% combining it with runtime libraries of Erlang/OTP as released by
+% Ericsson on http://www.erlang.org (or a modified version of these
+% libraries), containing parts covered by the terms of the Erlang Public
+% License (http://www.erlang.org/EPLICENSE), the licensors of this
+% Program grant you additional permission to convey the resulting work
+% without the need to license the runtime libraries of Erlang/OTP under
+% the GNU Affero General Public License. Corresponding Source for a
+% non-source form of such a combination shall include the source code
+% for the parts of the runtime libraries of Erlang/OTP used as well as
+% that of the covered work.
+
+-module(sg_asp_sup).
+-author('Harald Welte <laforge@gnumonks.org>').
+-behaviour(supervisor).
+
+-export([init/1, start_link/2]).
+
+init([Name, AsSupPid]) ->
+	%AsName = list_to_atom("sg_as_" ++ Name ++ "_fsm"),
+	StartFunc = {xua_asp_fsm, start_link, []},
+	ChildSpec = {xua_asp_fsm, StartFunc, permanent, infinity, worker, [xua_asp_fsm]},
+	% simple_one_for_one will not start any children!
+	{ok, {{simple_one_for_one, 10, 60}, [ChildSpec]}}.
+
+start_link(Name, Options) ->
+	supervisor:start_link(?MODULE, [Name, Options]).