export modules via the package json to enable better tree shaking

[goastler]

[goastler]

this needs to be done per package, exporting any individual components. E.g. the util package exports the lodash code as a single unit. It is a single module which can act as a library in its own right, so it should be exported itself. Chris has verified that this does get tree-shaken, so worthwhile doing!

[HughParry]

Prioritisation + complexity