GitLab

- Add Group For Selected Nodes
- Add Selected Nodes To Group
- Fit Group To Nodes

* improve image preview
- grid mode: align in rectangle instead of first image, show cell border
- individual mode: proper ratio handling

* improve: fix preview button position instead of relative

* improve: image preview - compact mode for same aspect ratio

Fix connecting combos of same type from different types of node

no longer uses combo list as type name

* Add toggle for float rounding

* Add manual precision override

It can be useful to paste images from the clipboard directly into the node graph.
This commit modifies copy and paste handling to support this.

When an image file is found in the clipboard, we check whether an image node is selected.
If so, paste the image into that node. Otherwise, a new node is created.
If no image data are found in the clipboard, we call the original Litegraph paste.
To ensure that onCopy and onPaste events are fired, we override Litegraph's ctrl+c and ctrl+v handling.

Try to detect whether the pasted image is a real file on disk, or just pixel data copied from e.g. Photoshop.
Pasted pixel data will be called 'image.png' and have a creation time of now.
If it is simply pasted data, we store it in the subfolder /input/clipboard/.

This also adds support for the subfolder property in the IMAGEUPLOAD widget.