Add context plots

[kbenoit]

Requested feature

Something to plot pattern matches in context. Options to explore:

• ggpage
• the approach used by rplos
• sentimentr::highlight()'s approach (see their example)

Could work with kwic output.

[yuanzhouIR]

Does this issue refer to plot a wordcloud or somewhat using the kwic output? I think it will be definitely helpful. I'm pondering how to visualize the context of some keywords. Maybe it's a good idea to convert the kwic output to a dfm and then plot it. Hope this feature comes soon!