adding subplot titles to make_subplots
adding subplot titles to make_subplots

Adds titles to subplots and insets.
@chriddyp @theengineear @etpinard @aneda @jackparmer

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