digishield difficulty retarget implemented

Conflicts:
	src/main.cpp
Checkpoint added
Copyright added

Conflicts:
	COPYING
	README.md
	doc/README.md
	doc/README_windows.txt
	src/qt/aboutdialog.cpp
	src/qt/forms/aboutdialog.ui
	src/qt/res/bitcoin-qt.rc
changed conditions for alert
enable ja
Fix total coins & difficulty retarget

Conflicts:
	README.md
Fix text