lib: Update list of company identifiers
build: Update library version
Release 5.4
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.
gatttool: Use GError to propage error messages to caller

Handle runtime errors outside gatt_connect(), using GError to propagate
error messages to caller.