improve supply dflts for grid
improve supply dflts for grid

-show line if `linecolor` or `linewidth` is defined
-show grid if `gridcolor` or `gridwidth` is defined
-show zero line if `zerolinecolor` or `zerolinewidth` is defined

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