java 8 + couple fixes

[razuz]

So here we go :

• added java 8 support
• improved java 7 install
• fixed PDF registry keys versioning
• fixed vmcloak install doesn't attach network on VirtualBox 5.1.2 and ubuntu 16.04 #74 - VBox 5.1 network connection "cable" is not connected by default any more
• adding some --debug noise related to Request: Improve VMCloak logging #55 so that debugging can be easier :)
• fix iso install fails when partitions exist #71
• add key --vramsize to init - dynamic video memory size ;) default is 16

Cheers !

[jbremer]

Lots of goodies in here - thanks!