Update substitution tokens for Google Drive

Made with:
replace 'https://freenet.googlecode.com/files/freenet-FREENETTAG-source.tar.bz2.sig' 'FREENET_SOURCE_SIG_URL' -- pages/*/*.php
replace 'https://freenet.googlecode.com/files/freenet-FREENETTAG-source.tar.bz2' 'FREENET_SOURCE_URL' -- pages/*/*.php
replace 'https://freenet.googlecode.com/files/FreenetInstaller-FREENETVERSION.exe' 'FREENET_WINDOWS_INSTALLER_URL' -- pages/*/*.php
replace 'https://freenet.googlecode.com/files/new_installer_offline_FREENETVERSION.jar.sig' 'FREENET_INSTALLER_SIG_URL' -- pages/*/*.php
replace 'https://freenet.googlecode.com/files/new_installer_offline_FREENETVERSION.jar' 'FREENET_INSTALLER_URL' -- pages/*/*.php

In the process of these substitutions concerning Google Code it became
apparent that the French FAQ and German download-old still link to the Google
Code SVN.