rigged functions should have a class

[moodymudskipper]

c("boomer_rigged", "function")

So we can recognized them easily.

• original environment is set as an attribute
• printing method will show it's rigged, and mention original environment/namespace
• is_rigged function checks if we inherit from "boomer_rigged"

rig_in_namespace will use it to make sure all function environments are synced, it will also make it easy to unrig, just set back the environment to initial value.