Just a small description of
plugins, what they are, how they work, and how to implement one.
To undestand how plugins work, you have to know how Folium template is made. Basically, it is made of four parts :
divs are defined there.
Now, a plugin is an object that inherits from
folium.plugins.Plugin, whose goal is to write things into these four parts.
Note that you may be willing to put on a map several instances of the same plugin. But you don't want the header to be written several times. This is why each method has a
nb argument, that will be incremented at each instance's render.
Hence the line
if nb==0 else ""
TODO : write something interesting here.