Added some tests for ringbufferwindow code.

Using 'check' library for unittesting.
Added tests for RingBufferWindow class
RingBufferWindow now fills in all packet seq numbers
Fixed memory allocation for ring buffer's packets
added tests for ringbuffer get_packet_n and get_next_packet
added tests for rbw_get_ack* functions
added tests for rbw_inc_head*
add tests for rbw_set_win_size
Added tests for ringbufferwindow

Unit tests added:
* rbw_get_ack_n
* rbw_get_get_ack_of_packet
* rbw_inc_head
* rbw_inc_head_to_packet
* rbw_set_win_size
Added Boiler code from Moodle for server and client
Updated src/Makefile to build both server and client

* Note that nether build ATM
* Fixed #include bug in given code
Merge branch 'gpoisoned'

Conflicts:
	src/GBNclient.c
	src/gobackn.h
	src/ringbufferwindow.c
	src/sendto_.h
Implemented gbn_copy
Gave meaningful names to variables in sendto_.h
Moved code in sendto_.h to sendto_.c
Fixed various includes
Improvements to ringbufferwindow

* Added win_last_frame for convenience
* rbw_set_win_size now clears packets out-of-window if window shrinks.
* rbw_inc_head and rbw_int_to_head clear packets out of frame
* added rbw_get_n function for getting the offset of the given packet to head
gbnp_copy now copies all data
First implementation of GBNserver
Added functionality to create packets