Create numbered and bulleted lists

This PR aims to add the creation of lists in a document. This only aims to support numbered and bulleted lists and not image bullet lists for now.

# TODO
* [x] Editor UI buttons
* [x] Detect list style at selection
* [x] Ops for list insertion/removal
* [x] OT support
* [x] Convert selected text to a list or selected list back to text
* [x] Add feature flags and session constraints
* [x] Default styles for numbered and bulleted lists

This looks like a merging mistake trying to follow the change from `Editor.js` to `wodotexteditor.js`: there is no more a `editorOptions.unstableFeaturesEnable` parameter, and the `isUnstable` is only needed for the collab editor class variant. Please revert this.