Fixed README grammar error

Added more detail to the Dataset Modifications section in README

Fixed typo for the full name of DMOS

Fixed the broken links to the dataset preprocessing scripts

Reverted koniq-10k/labels.csv to using the official splits info

Updated README.md's description of the "set" column

For those without official splits information, the splits have been generated randomly following a ratio of train:val:test = 72:18:10.

Updated README.md to add a note about KonIQ-10k

Updated README.md to use the new URL for the dataset scripts

Added BID, CSIQ, KADID-10k, LIVE, and LIVE In the Wild datasets

Added KonIQ-10k images and labels

initial commit