:hocho: annotation/shape/image extra defaults step for category axes
:hocho: annotation/shape/image extra defaults step for category axes

... in Plots.doCalcdata

- this approach was flawed: led to position value not updating
  properly on calc-less update (e.g. zoom/pan)

plotly/plotly.js,etpinard/plotly.js,etpinard/plotly.js,plotly/plotly.js,iongroup/plotly.js,asolagmbh/plotly.js,asolagmbh/plotly.js,plotly/plotly.js,asolagmbh/plotly.js,plotly/plotly.js,iongroup/plotly.js,aburato/plotly.js,iongroup/plotly.js,etpinard/plotly.js,aburato/plotly.js