modified httpdown.erl
modified
use callback module in httpdown
modified version
modified version
modified version
adding show prograss in console
modified test Uri in fuction that httpdown:start()
adding http_to_file for storing downloaded data
storing date into file--
if file has downloaded,then return {error,{file_exist,FileName}}
logging.c/loggin.h
add new files
add files for thread class
Merge branch 'develop' of https://github.com/shaxunyeman/dbliu

Conflicts:
	base/criticalsection.h
	base/logfilestream.cpp
	base/logfilestream.h
	base/logging.cpp
	base/logging.h
	base/stream.h