I decided to go down to Fort Independence to trade all the Laser Pistols and Scrap Metal I had been building up since I started my save file, but I can't get near Fort Independence without the Outcasts trying to waste me, and I I haven't done anything to make them mad.

Well, I did encounter a hostile squad of Outcasts not far from the Super Duper Mart (and I wasted them in self defense), and I'm not sure if that was what did it or not.

Anyway, is there a console command or better, an ingame way to get the outcasts to not hate me?

Might be a long shot, but I think if you are carrying advanced tech before they ask you to bring it to them, it pisses them off. Try dropping the stuff then talking to them.

However, there is a setally faction command to use to make them an ally to another faction, in this case, you the player.

About 1/3 of the way down

http://fallout.wikia.com/wiki/Gamebryo_console_commands

I tried both, didn't seem to work.

I did start a new save file and that did seem to flush the bug, though I have no idea what caused it.

That happens to me occasionally as well. For some odd reason, every once in awhiile If I reload a save, my Enclave soldiers that I have made friendly (I use a mod to set me to be allied with the Enclave) suddenly turn on me.

When I reload the save, it fixes the problem.

Go figure.