gatt: Keep track of registered characteristics
unit: Add a test for child objects to test-gdbus-client
core: rename gatt.h to gatt_lib.h

Cosmetic change to avoid misleading between gatt library header and
the core generic attribute API header.
core: Avoid connection attempt if adapter is down

This patch avoids automatic ATT connection if the adapter is powered
off.
core: Removed unused parameter

This patch removes the unused "psm" parameter in
device_register_primaries function.
core: Remove unneeded inclusion of hcid.h
core: Remove security level for service discovery

GATT service declaration shall be discoverable without security
restriction. Besides that all the calls are using low security level.
gatt: Introduce helper for adding GATT services

This patch adds the btd_gatt_add_service() helper which adds a
GATT Service declaration to local attribute database.
gatt: Introduce helper for adding characteristics

This patch adds the btd_gatt_add_char() helper which adds a
characteristic (both declaration and value attributes) to local
attribute database.
gatt: Introduce helper for adding characteristic descriptors

This patch adds the btd_gatt_add_char_desc() helper which adds a
characteristic descriptor to local attribute database.
gatt: Introduce helper for removing services

This patch adds the btd_gatt_remove() helper which removes a
service (along with all its characteristics) from the local
attribute database.
gatt_lib: Add a way to request read by type over a range of handles

This introduces gatt_foreach_by_type(), which will allow to iterate
over a range of attributes of known types.

This will be mostly used for the new discovery of attributes.
device: Add a way to retrieve the device's attribute database
device: Add device_get_attrib()
gatt: Add stub for gatt_discover_attributes()
gatt: Add support for inserting Include declarations
gatt_lib: Add a way to call Find Information over a range
gatt: Insert the characteristics descriptors in the database
device: Discover all the attributes of a device
gatt: Register Attribute D-Bus interfaces