Removes some unnecessary includes from `editor_node.h`, and instead add
those where they're used.
Removes unnecessary `editor_node.h` includes in various editor classes.
Renames `dynamicfont` to `dynamic_font` in a couple files.
Misc cleanup while jumping through that rabbit hole.
Allows configuring the MultiplayerSynchornizer in a way similar to
AnimationPlayer.
Properties are added manually, edither as plain properties, or via the
NodePath format for child nodes' properties "path/to/node:property"
relative to the MultiplayerSynchronizer root path.
Nice things to add would be:
- Moving properties up/down in the list.
- Some form of keying, autmatic filling of the replication properity
line edit.
