Results of the second Palapeli hackathon (again basically me in a train for several hours):
* Complete the new action-based interface with the the four actions "Create", "Delete", "Import", and "Reset".
* Register a application/x-palapeli-puzzle mimetype for extension *.pala
* Add a CLI interface to handle application/x-palapeli-puzzle, integrate into KonqPopupMenu.
* Add a welcome widget to ease the first steps.
* Add a simple loader widget to reduce the flicker.
* Turn Palapeli::LibraryStandardBase into a singleton. Implement insertion and removal of entries in LibraryBase class.
* Add a LibraryFilter (subclass of QFilterSortProxyModel) to show only removable items on a LibraryView.
* Change the main config file format to allow for easier creation of puzzles.
* Add a Palapeli::Pattern::Mode enum to gain the ability to simulate slicing (necessary to get the piece count).
* Remove cmake/ directory, FindPalapeli.cmake is in lib/ now.
* Fix many issues, and report more issues in "//TODO:" and "//FIXME:" comments.