tools: Fix mpris-player not forwarding method calls properly

This fixes not sending methods calls to players, it now copies the
contents of the original message into the copy instead of relying on
dbus_message_copy and send the reply back.
obexd: Fix make distcheck

../obexd/client/map.c:43:17: fatal error: sdp.h: No such file or directory
attrib: Simplify boolean tests

Remove unnecessary TRUE/FALSE in boolean tests.
attrib: Change GAttrib->stale type from gboolean

There is no reason to GAttrib->stale be gboolean.
attrib: Change command->sent type from gboolean

There is no reason to command->sent be gboolean.
attrib: Change is_response return type from gboolean

There is no reason to use gboolean as return type of is_response.
attrib: Change match_event return type from gboolean

There is no reason to use gboolean as return type of match_event.
attrib: Change g_attrib_set_destroy_function return type

The return type from g_attrib_set_destroy_function don't need to be
gboolean, it can be standard bool type.
That change implies change in its signature, which requires stdbool.h to
be included where attrib/gattrib.h is included.
attrib: Change g_attrib_cancel/_all return type

These functions doesn't need to use gboolean as return type.
attrib: Change g_attrib_unregister/_all return type

There is no reason to use gboolean in return type for these functions.
attrib: Change g_attrib_set_debug return type from gboolean

There is no reason to use gboolean in return type of g_attrib_set_debug.
attrib: Change g_attrib_set_mtu return type from gboolean

There is no reason to use gboolean in return type of g_attrib_set_mtu.
attrib: Change g_attrib_is_encrypted return type from gboolean

The function g_attrib_is_encrypted don't need to use gboolean as return
type, it can be standard bool type.
This change implies that gatt_channel->encrypted from
src/attrib-server.c can be standard bool type too.
attrib: Change command->opcode type from guint8

Change type of command->opcode, command->expected and event->expected
for a standard type.
attrib: Change event->handle type from guint16

Change type of event->handle for a standard type.
attrib: Change command->id type from guint

Change type of command->id and GAttrib->next_cmd_id for a standard type.
attrib: Change event->id type from guint

Change type of event->id for a standard type.
attrib: Change command->pdu pointer type from guint8

Change pointer type of command->pdu for a standard type.
attrib: Avoid passing raw PDU to Exchange MTU callback

By centralizing the PDU parsing and validation internally to GATT API,
the callbacks become simpler.
unit: Add test for gatt_exchange_mtu()

The new unit/test-gatt.c file will contain tests for GATT API
implemented in attrib/gatt.{c,h}.