Path tool points manipulation: nudging, drag axis snapping, and G/R/S (#1068)

* issue820: implemented nudging points

* nudge points triggered only when the mouse is moved after selecting one point

* issue 820 // bullet 1 done

* grab working / rotate not

* rotate works (sensitive)

* G/R/S and Shift/Drag working

* Cargo formatted // implemented Hypercubes comments

* Refactored G/R/S - need to fix fast transform

* Finished refactored G/R/S

* Typed Angle needs further touch up

* Cargo formatted

* Dealt with dangerous unwraps

* Cargo fmt (again) - unwraps fixed

* Cleaned up

* cargo fmt

* Ready for Review

* Ready for Review- cargo fmt

* Code review fixes

* Remove duplicate constant for nudging

* Fix consts.rs spacing

* Apply suggestions from code review

Added suggestions

Co-authored-by: Keavon Chambers <keavon@keavon.com>

* Added typo/grammar suggestions

* Nits

---------

Co-authored-by: Shiro <shiro@damedane.local>
Co-authored-by: hypercube <0hypercube@gmail.com>
Co-authored-by: 0HyperCube <78500760+0HyperCube@users.noreply.github.com>
Co-authored-by: Keavon Chambers <keavon@keavon.com>

document-legacy/src/operation.rs

@@ -4,6 +4,7 @@ use crate::layers::layer_info::Layer;
 use crate::layers::style::{self, Stroke};
 use crate::LayerId;
 
+use graphene_core::vector::SelectedType;
 use graphene_std::vector::consts::ManipulatorType;
 use graphene_std::vector::manipulator_group::ManipulatorGroup;
 use graphene_std::vector::subpath::Subpath;
@@ -141,7 +142,7 @@ pub enum Operation {
 	MoveManipulatorPoint {
 		layer_path: Vec<LayerId>,
 		id: u64,
-		manipulator_type: ManipulatorType,
+		manipulator_type: SelectedType,
 		position: (f64, f64),
 	},
 	SetManipulatorPoints {