* updated package.json.
 * updated gitignore.
 * fixed reference in icons.less for chanzhi build.
 * added real checkbox input to datatable support checkable.
 * enhanced messager.
 * added show function to $.messager.
 * messager can display on the center of the screen.
 * updated document for messager.
 * return the messager object when call a quick show method.
  * reset padding value of ol and ul.