[Single WebEntity] Add a "Related Entities" tab displaying related entities

[boogheta]

This could include child/parent ones, but also citing/cited ones, and allow easily to merge one into the current with a single button as with latest HyBro changes
This should provide insights on the distribution of tags, as well as other measures such as indegree

TODO:

• fix issue with disabling IN entities
• design the whole tab menus
• add the list of displayed entities similarily to the page LIST WEs
• update network on update settings instead of reloading it ?
• handle filtering cases with no entities to display
• add filtering and coloring by tag value for each existing category
• handle sigma stacktraces
• what about darker links in network?
• Check Clean extra Set functions added within the code #368
• display a webentities list of PROSPECTS related to the entity if it has some crawls (within the Crawls tab or within the related entities one?) (cf Add a "latest prospects" feature in corpus #420)
• button to export the csv list of connected entities (was [Single WebEntity] Add export buttons #318)

WIP in https://github.com/medialab/hyphe/compare/better-ego-network?expand=1