Simple fixes

Two changes:

 1) Remove the `eval`
 2) Remove the RAM estimate. It's a very complicated piece of code that yields an extremely
     inaccurate estimate of the RAM requirements. For example, a simple
     IGO is estimated at around 9MB, but calling build() creates around
     60MB. For things like HOGs it makes it seem as if you have enough
     memory when you probably don't!