Revert "Moved native code to jni/"

This reverts commit 845b68b4e1db86af482c32205a3541bc31b6facc.
Set preferences title to Settings
* Moved Set DNS to menu
* Added Start/Stop menu item (in progress)
* Use switch to check for clicked menu item
Avoid blocking app while connecting to gogoc

TODO: statusConnection should be moved to some sort of service
Use a single button for start/stop
Move all constants to Constants class
Move most of the gogoc control & shell methods to GogoCtl class

* Remove unused setPermission method.
* Also moved showToast & showDialog methods to GogoCtl class.
Moved statusConnection method to GogoCtl class

* Removed calls to showIndicator from statusConnection method, instead
  it is called after every call for statusConnection
* In case of connection establishment, set return of statusConnection
  to: established <IP6 addr>, and showIndicator method then uses
  substring to print <IP6 addr> to status text box
Set address text field to focusable, to allow users to copy the IPv6 address