improve algorithm (part 2):
improve algorithm (part 2):

- init grid cell indices (i,j)
- start subplot counters at 1 (the plotly way)

plotly/plotly.py,plotly/python-api,plotly/plotly.py,ee-in/python-api,plotly/python-api,ee-in/python-api,plotly/python-api,ee-in/python-api,plotly/plotly.py