I don't foresee that to happen because, according to Apple, the camera roll isn't meant as an archive folder. Photos taken using iPhone should be synced to a computer for archiving/editing/etc...
Then, for example, in Photos for Mac, you can set up folders and what not and sync those to iPhone.
Now you're probably wondering "i have to move my images from my iPhone to my computer then back from my computer to my iPhone?"and you're probably right, but Apple envisioned the process this way.
Those were my 0.02$ on the matter, I may be mistaken!
iOS Transfer, Manage iOS Devices Easily & Effortlessly. Do you MOVING photos from your iPhone Camera Roll into folders, will Apple finally hear us & add MOVE too in Apple Photos. Go to: https://tunesgo.wondersha