design fixes in html for getting started pages

[cldougl]

• rm extra title: "Getting started with Plotly for --- " (doubled now cause of the autogenned header)
• edit header for getting started pages so the links work when they're clicked
  • [ ] https://plot.ly/javascript/getting-started/
  • [ ] https://plot.ly/scala/getting-started/
  • [ ] https://plot.ly/python/getting-started/
  • [ ] https://plot.ly/pandas/getting-started/
  • [ ] https://plot.ly/nodejs/getting-started/
  • [ ] https://plot.ly/matplotlib/getting-started/
  • [ ] https://plot.ly/matlab/getting-started/
  • [ ] https://plot.ly/r/getting-started/