install samtools on Ubuntu(gcc -c -g -Wall -O2 -D_FILE_OFFSET_BITS=64 -D_LARGEFILE64_SOURCE -D_USE_KNETFILE -D_CURSES_LIB=1 -I. bgzf.c -o bgzf.o In file included from bgzf.c:36:0: bgzf.h:29:18: fatal error: zlib.h: No such file or directory compilation )

I just found a way to solve this problem:

http://ubuntuforums.org/showthread.php?t=1632027

To put it simple,
First:  sudo apt-get update
Second:  sudo apt-get install zlib1g-dev libncurses5-dev
Third: make  #this is the step to restart the samtools installation

Done!