* Removes TNT Unicode controls, which are no longer required. All VCL controls now have native Unicode support.
* Remove Delphi 11 packages, otherwise we would either need to keep TNT or break Unicode
* PngComponents update from Uwe Raabe on http://cc.embarcadero.com/Item/26127
* Adjust auto build process
* Since Delphi 2009, Strings are now UnicodeStrings, not AnsiStrings any longer. Fix a bunch of compiler errors which came along with this change.
TODO: Project should compile but give tons of compiler warnings.
* Use this chance to add a confirmation dialog when leaving the editors, to ask the user if he wants to save modifications. Fixes issue #1524.
* Also, enhance Mainform.RefreshTreeDB in a way that it does not trigger the OnFocusChange event. Important for the editors when saving changes.
