1. add config module, which contain a class Config. Config is used to
parse configuration from the config file. the default config file is
eye.in.
An example of config file:
[General]
#the unit of time is minute
rest_time = 5
work_time = 55
image_file = rei.jpg # or full path like C:/figure/rei.jpg
2. add a config window. When you click the 'config' menuitem in tray,
the window will be opened. the feature has not been finished