finished note
Merge branch 'yuwei' into note
Merge branch 'note'
edit README about notice
Merge branch 'yuwei' into note
Merge branch 'note'
modify note
Merge branch 'yuwei' into note
Merge branch 'note'
finish my note
Merge branch 'liulijia' into note
add fetch in README
add some words about fetch in REDME.md
Merge branch 'yuwei' into note
Merge branch 'note'