This fills the gap left by the ability to move vertices after creation, but not edges. This finally makes it possible to rearrange a diagram non-destructively.
It's now possible save and load direct links to diagrams. This makes it much easier to share commutative diagrams (given that it is not currently possible to import tikzcd code).
This will be ignored by git when working with the repository as-is, but src subtrees of the repository (for directly cloning the source) will now also have access to the submodules.
This adds a comprehensive history system for all of the actions *quiver* currently supports. I've made these interactions feel as natural as I can, but there'll undoubtedly be some tweaking remaining later.
Multiple cells can now be selected by holding Shift while selecting. Command (+ Shift) + A will (de)select all cells. This allows cells to be moved and modified en masse.
`forge_vertex`, switched on by default, allows you to draw an edge between empty cells (technically *to* an empty cell, but a new behaviour allows to drag from an empty one too), which will create the necessary vertices and edges. This allows diagrams to be created simply by dragging (and concrentrating primarily on the edges rather than the vertices).
This significantly increases the power of the edge styling, allowing for combinations of edge styles. Currently there is one extra tail style: `maps to`.
Default edge offset is now chosen in a similar, but more restricted, manner to label alignment, which makes the experience of creating diagrams with parallel arrows more natural.
This is as opposed to the previous behavior, where it would always focus the label input, making it more awkward to edit the cell as a whole (say, to delete it).
