I will write a detailed guide when I have more time to, I've been Jungling a bunch of different builds with Fiora since she was released and I'm liking this the best so far. The last few items are just suggestions, really the game usually ends before I can build beyond the bloodthirster and this build will make people call you OP if executed well (and not against heavy cc teams who focus you!)

Also skill sequence depends on how soon you want to gank, having your lunge is nessacary if you want to pick up a kill but not at all helpful jungling so if you are going to gank at level 3 take it if not I suggest a 2nd rank in burst of speed first.

For a very heavy cc team something like quicksilver sash or banshee might be a good idea as that one cc counter could be all you need to get your ult off and shred a few of them at once. :)