Bump README for v4.x
Bump README for v4.x

cliqz-oss/browser-ios,cliqz-oss/browser-ios,cliqz-oss/browser-ios,cliqz-oss/browser-ios,cliqz-oss/browser-ios,sharath-cliqz/browser-ios,sharath-cliqz/browser-ios,cliqz-oss/browser-ios,cliqz-oss/browser-ios,sharath-cliqz/browser-ios,sharath-cliqz/browser-ios,sharath-cliqz/browser-ios,sharath-cliqz/browser-ios,sharath-cliqz/browser-ios,sharath-cliqz/browser-ios,cliqz-oss/browser-ios