Topological order

The idea is to sort addins in a topological order. Each addin can define one of five things for _order_:
* `>X` - I must be immediately after the addin with id X

* `>>X` - I must be somewhere after the addin with id X (but not necessarily immediately) 

* `<X`- I must be immediately before the addin with id X

* `<<X` - I must be somewhere before the addin with id X (but not necessarily immediately) 

* `Number` - A numerical order which is used if none of the above is applicable


good point. i should not write code when i'm tired :) but i'm always tired!!
use the same structure with nested _.find then
it will be as optimized (stop on found, similar to break/return) and you'll even have a nice exit point out of the function with the returned value from the find operation.