Implement cut tool

yeah that was the easy part but still

- Added hotkeys for copy, paste and cut
- Added _copyPaste.js for copy, cut and paste management

js/_copyPaste.js

@@ -0,0 +1,21 @@
+let clipboardData;
+
+function copySelection() {
+	
+}
+
+function pasteSelection() {
+	imageDataToMove = clipboardData;
+	updateMovePreview();
+}
+
+function cutSelectionTool() {
+	// Getting the selected pixels
+	clipBoardData = currentLayer.context.getImageData(startX, startY, endX - startX + 1, endY - startY + 1);
+
+	currentLayer.context.clearRect(startX - 0.5, startY - 0.5, endX - startX + 1, endY - startY + 1);
+	// Moving those pixels from the current layer to the tmp layer
+	//TMPLayer.context.putImageData(imageDataToMove, startX + 1, startY);
+
+    //originalDataPosition = [currentPos[0], currentPos[1]];
+}