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                            Interactive plots
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In previous exercises we focused on static and animated plots. 
We now move to so-called interactive plots.

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We will focus on a few python libraries:
- mpld3     http://mpld3.github.io
- pygal     http://www.pygal.org/en/stable/
- plotly    https://plotly.com/python
- Bokeh     https://docs.bokeh.org
- HoloViews http://holoviews.org
- Altair    https://altair-viz.github.io/gallery/index.html#interactive-charts

* you can use also one other extra library (if you find it as useful as those above)
* for installing libraries ue can use Virtual Environment
https://docs.python.org/3/tutorial/venv.html

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The task:

From the six libraries above choose three.
Next using each library generate two, separate, interactive plots 

For instance:

mpld3_plot1_data1.py
mpld3_plot2_data2.py

pygal_plot1_data3.py
pygal_plot2_data4.py

bokeh_plot1_data5.py
bokeh_plot2_data6.py

(Six plots in total)

You can use the data from previous exercises, but you do not need to.
You are not allowed to use examples from libraries tutorials/galleries 
(obviously, you can use them for learning purposes).

Hint: frequently the data used for making animated plots can be easily 
transformed into the interactive plot, but it may require to move to 
different plot type e.g. bar plot with time (the dimension upon we 
updated plot for population) can be scatter plot with tooltips


Additionally, the scripts should have one positional parameter [0/1] for showing or 
saving the plot.

For instance typing in the terminal: 
python plot1.py 0      [will show the plot in interactive mode, plt.show()]
python plot1.py 1      [will store the plot in the file and print the path to the file]