Update README: Copy chromedriver into ./assets
Update README: Copy chromedriver into ./assets

Copying chromedriver only into `instagram-profilecrawl` root, gave me errors (`chromedriver` wasn't found even when linked in PATH). I had to copy it into `instagram-profilecrawl/assets` (first creating the directory). I run Windows 10 64x.
timgrossmann/instagram-profilecrawl,timgrossmann/instagram-profilecrawl