Nerf Pilot Barrel Attachment Lug

I couldn't find anything that does this so I made my own, based off of CJdoeshobbies's [muzzle adaptor](https://www.thingiverse.com/thing:5846319). I really like how it turned out.

Tested and works great with most attachments. Remember to always use [barrel spacers](https://www.thingiverse.com/thing:6530788) for a tight fit and no wiggling.

The body should friction-fit well enough for casual usage (and will still be easily removable), but there's a screw hole in the bottom for affixing it more firmly.

Included is a version with two clips for holding shells. I like to use [shells that you have to remove to reload](https://www.thingiverse.com/thing:6675973), so the clips make reloading much more convenient. They're optimized for my shells (link above) but should hold any pilot-bore shells decently. If you don't want the clip then use noclip.stl instead of the other files.

Rival/Mega ammo will still fire as normal with this attached, but do note that most barrels won't work wi