Bugfix for e-p+ colliders

This patch release fixes two bugs:

• Added symbols for e-p+
• Fixed link in interactive_charts.py

First Data Set + Interactive Charts

This is the first set of "historical" accelerator data and includes the following features:

• Data (in csv file)
• export_charts.py: Export plots via matplotlib
• interactive_charts.py: Interactive plots via plotly (local and in documentation)
• Setup of documentation via Sphinx/Sphinx-Gallery