Initial import memory manager
Merge remote-tracking branch 'remotes/local_v/memory_manager'
* changed pico_free into PICO_FREE
* changed pico_zalloc into PICO_ZALLOC
Added 2 missing architecture files (pico_avr.h and pico_str9.h)
Added two new architectures in the Makefile:
    * AVR
    * STR9
Fixed compiler warnings for modules/pico_mm.c
Fixed compiler warnings
Merge branch 'master' of https://github.com/tass-belgium/picotcp

Conflicts:
	modules/pico_arp.c
	modules/pico_dhcp_client.c
	modules/pico_dns_client.c
	modules/pico_http_server.c
	modules/pico_http_util.c
	modules/pico_icmp4.c
	stack/pico_device.c
	stack/pico_socket.c
	stack/pico_tree.c
	test/units.c
Fixed some warnings
Undo changes last commit
Removed forgotten pico_mem_init
Added missing PICO_FREE
Merge branch 'master' of https://github.com/tass-belgium/picotcp

Conflicts:
	include/pico_config.h
	modules/pico_dev_loop.c
	modules/pico_dhcp_server.c
Merge branch 'master' of https://github.com/tass-belgium/picotcp

Conflicts:
	Makefile
	include/pico_config.h
	modules/pico_dev_null.c
	modules/pico_dev_pcap.c
	modules/pico_dev_tun.c
	modules/pico_dev_vde.c
	modules/pico_http_client.c
	modules/pico_ipv4.c
	modules/pico_tcp.c
	stack/pico_device.c
	stack/pico_socket_multicast.c
	test/picoapp.c
Merge branch 'master' of https://github.com/tass-belgium/picotcp

Conflicts:
	modules/pico_http_server.c
	modules/pico_icmp6.c
	modules/pico_tcp.c
	stack/pico_socket.c
Removed some hacks
Merge branch 'master' of https://github.com/S4mw1s3/picotcp into S4mw1s3-master
Removed stale printfs
Removed stale printfs
Added option to run in MM