Start Working on http_client

need to working on send request and parse for returned info
Correct implementation for part1

Tried the ./http_client k www.cs.northwestern.edu 80 /index.html  here
is the simple output
Part1 almost done

Problem receiving data, fatal error (if we only get the content, it
works fine, not when read HTTP headers)
Part1 Done

Part 1 running well on T Lab. Please test it and compare with the
correct bin file
Update README.md

Part1 done
Update README.md
Start working on part2

server1 is now able to do listening (up tp 5 in the queue)
Part2 Done!

Need to test!
Update README.md

Part2 done, but have bug:*** glibc detected *** ./http_server1: double free or corruption (out): 0x00007fffc8a410f0 ***
Part2 done! And tested!

The former bug is free char* . Because the system will try to take care
of them, so I just common these code and fixed it
Update README.md

Part2 Done! Yeah!
Part3 begin

Inherited all functions from part2
Part1 small modification

Configured the minet_select part
Part3 done, needs test

BACKLOG may not need to be that big, we can still set it back to 5.
Please test Part1, 2, 3. If there is any bug please e-mail me
immediately :)
Update README.md
Merge pull request #1 from LeiWangHoward/master

Got part1 and part2 done!