gallery runs (almost)
begin porting tutorials
working on manual
More work on tutorials.
Make it clear that Point is an instance of Additive.
Fix type on 3D.
Changes to Core.Points.
update manual for linear migration
remove some text which is misleading for `linear`
fix typos in docs
Some fixes to manual.
manual: fix some RST syntax warnings
Merge pull request #65 from diagrams/linear

Migrate from `vector-space` package to `linear`

Make types more polymorphic.