test: use pkg-config for cpputest build flags

btstack_memory: refactor generator code

hci: define periodic_advertiser_list_entry_t

test: only compile CppUTest files with c++ compiler

btstack_debug: add c++ guard

tool/btstack_memory_generator: update copyright, fix deinit

test: fix c/c++ mixed compile warning, streamline makefile

hids_client: skeleton code for connect

scan_parameters_service: implement write without response for scan parameters

test/btstack_memory: fix test for newer gcc

ble/battery_service_client: implement query services

test: remove HAVE_ASSERT from coverage tests

test/btstack_memory: cover no buffers, single buffer, and malloc configurations