Improvements to Network Graph for word meanings

[avkoehl]

• Add tabular data to left hand or right hand side
• Improve hover info readability (reduce number of decimal points, add descriptive word, e.g word count: 3,812 instead of just 3812
• Add dropdown to select number of nodes to draw
• For decades, instead of dropdown do slider like for the topic model
• Set seed before drawing the graph - so that results are consistent.