MiniPauker Code

Fixed broken storing of the current session name.

- Major refactoring:Im.ExportController, LearningC. extracted out of the UIController
- UIComponents now calls updateView on itself before displayed (or before displaying an alert that will be replaced by the UI) => no more need to tell it it needs to update itself, plus only the visible component updates itself =>
--Fixed #2349680 - Answer is shortly shown when "remembering"

Major refactoring (yet to be thoroughly tested):
- ImportExportController and LearningController extracted out of UIController
- Introduced PaukerDisplay for centralizing view management
- In tasks, switched from prev/next Displayables to the use of ViewNavigation
- UIComponent now calls updateView itself before being displayed
- Repeat Expired/Unlearned highlighted when they are non-empty (works only partially, namely the highlighting disappears e.g. when the item is hovered over)
- Open / Import UI: refactoring for better readibility incl. replacement of item indexes with their labels in action handling

- Refactoring: PaukerPrefs and CardBatches factored out from PaukerCore
- Swapped Cancel and Save&Quit buttons in the save dialog to correspond to the normal meaning of the keys
- Added the option to automatically load the previous session upon startup

1. Fixed bug 2995756 (cards can't go to batch 8 - a missing break in a switch)
2. PaukerPrefs factored out from PaukerCore.

created basic intro for developers

updated version # in help.txt

removed version # from screen title

builds special -debug version if test=true, version as property

show an info when show log invoked but log not enabled during compilation (see build.xml - <debug ...>