www/devmaster/lesson*.html: Fix header, title, navigation and links.

Signed-off-by: Xerxes Rånby <xerxes@zafena.se>
Merge remote-tracking branch 'xranby/www'
Merge remote-tracking branch 'xranby/master'
www/index.html: Switch github -> jogamp link to source for lessons 1,2,3,5 & 8

Signed-off-by: Xerxes Rånby <xerxes@zafena.se>
www/devmaster/lesson*.html: Fix relative jnlp links.

Signed-off-by: Xerxes Rånby <xerxes@zafena.se>