Update 124 - weapon racks and improved controls?

- added the larger weapon racks, the electric racks are not entirely supported by the copy-paste plugin, wiring isn't included on rust import and it won't export those prefabs at all


- added "level camera movement" in options, default w/s movement is on the left above, holding left alt toggles this on (or off if the option is enabled), this can be changed to another key in the startup input panel


- added visible colliders for the vertical barrel and hitch trough to help with placement, any other deployables need this?

symmetry mode improvements
- symmetry center data is now saved
- optimized the "add symmetry" tool which was pretty slow, spawning symmetrical parts and overlap replacing everything, now it checks for symmetrical parts at the expected position before spawning new ones
- fixed merge causing symmetry center to not be set

fixed undo/redo bugs
- moved parts that were then deleted
- symmetry with certain edit mode tools
- pipe mesh not being rebuilt after undoing a move

- added a check for underground copy-paste imports, moves everything to the surface

- changed LMB drag selection, before holding alt was needed to deselect with this, now just dragging over already selected parts does that

- improved visual range shader, more transparent edges, definitely needed for orthographic mode

- updated wind turbine prefab path for copy-paste exports, FP changed this recently

- fixed a bug where newly placed parts would sometimes show zero stability in the mouse over text

- added a menu link to the fortify youtube page, I'm planning on adding tutorials someday


The new camera movement option is probably what should have been default from the start, I was just stuck in my ways with 3D modeling controls. Let me know what you think.