RFR: JDK-8140268 Update link to license information in Javadoc

[Magnus Ihse Bursie]

The links to the Javadoc specification license needs to be updated for JDK9.
Bug: https://bugs.openjdk.java.net/browse/JDK-8140268
WebRev: 
http://cr.openjdk.java.net/~ihse/JDK-8140268-javadoc-license-link-footer/webrev.01

/Magnus