Bad URLs in README.md:Verifying Fred builds

[gresskar]

From Verifying Fred builds

wget https://downloads.freenetproject.org/alpha/freenet-ext.jar -O FreenetReleased/freenet-ext.jar
wget: bad address 'downloads.freenetproject.org'

wget https://www.bouncycastle.org/archive/159/bcprov-jdk15on-159.jar -O FreenetReleased/dependencies/bcprov-jdk15on-1.59.jar
wget: server returned error: HTTP/1.1 404 Not Found