initial commit, based on htwg.se.sudoku
added .project etc.
pulled in changes made in de.htwg.se.sudoku.
included resize in option menu from de.htwg.se.sudoku
Implemented db40, DAO, save and load functions
added load and save dialog and the possibility to generate playgrounds
from loadDialog
Merge remote-tracking branch 'origin/db4o_database' into db4o_database

Conflicts:
	de.htwg.sa.sudoku/src/de/htwg/sudoku/aview/gui/SudokuFrame.java
added jar for db4o and changed file location for database
renamed persistence layer and DAO
added classes affected by the renaming
Find Naked Single works as plugin within same project
moved from de.htwg.sa.sudoku
moved plugins to extra package
removed solvers and moved them to their own project
added plugins.jar
Merge remote-tracking branch 'origin/master'