This change fixes the block count report, and also makes
naturalize act more like a "//replace dirt grass" where
we only attempt block changes if the block is not already
what we're looking for.
- Move Vector, etc. into `.math` package
- Drop many methods that will be auto-promoted anyways, eg. with
`divide(int)` and `divide(double)` the first is now gone.
- Take Block vectors into their own class hierarchy
- Make it clear throughout the API what takes blockvectors
- many more improvements
This converts the project into a multi-module Gradle build.
By default, Git does not show history past a rename, so use git log
--follow to see further history.
