Unify tooltips for mousing over data in visualizations

[danicahelb]

tooltips have different styling

histogram:

bar:

scatter:

boxplot:

line:

updated tooltip for line (as of b62): see VEuPathDB/EdaNewIssues#547

[danicahelb]

Paused until line plot tooltips are finalized. see https://www.figma.com/file/kF2dYzNAwEiHW8Khxo6B1I/Lineplot-undefined-(ie%2C-0%2F0)-proportions?node-id=52%3A449&t=wIH37UgCbs61eeFt-0

[danicahelb]

info from @moontrip

for your information about your two screenshots of other Vizs' tooltip text style, the histogram one is made of a manual tooltip text and the scatter plot one is a default tooltip text style at plotly without specifying tooltip texts. So, if one sets up a manual text to the Scatter plot, then yes it can be similar to the histogram one, I suppose.