Builtin plugins should be statically linked

[evan2645]

It doesn't make a ton of sense to have standalone binaries for plugins which ship by default. It also complicates the build process and security story. Instead, we can statically link plugin logic in the agent and server binaries. Your mission, if you choose to accept it, is to teach the plugin catalog about builtins, and link them in directly. It should support both compiled-in builtins and bring-your-own for every plugin type.

[evan2645]

hey look, this is done!

#360 and #364