fix bugs of host_empty not show
Merge branch 'master' of github.com:JackonYang/snipmate
nomarl host axis save in axis_host
ovs axis saved in axis_ovs
special host axis save in axis_host
draw line only once
simplify lines between
deep simplify lines between ovs
deep simplify lines including host
update notes
unify links between host and ovs
remove unreferenced variable