Javadoc fixes after testing with JDK 14 build 36

apps/addressbook/java/src/net/metanotion/package.html

...bapp/src/main/java/net/i2p/imagegen/IdenticonServlet.java

...rypto/eddsa/math/ed25519/Ed25519LittleEndianEncoding.java

core/java/src/net/i2p/data/i2cp/package.html

router/java/src/com/maxmind/geoip2/DatabaseReader.java