Add tab control so you can display several collections at once.
Remove singleton cache, add cache in each CezanneForm.
Flush cache when closing tab.
"CezanneLib" => "Cezanne.Lib"
"CezanneTest" -> "Cezanne.Test"
"CezanneForms" -> "Cezanne.Forms"
Rename folders.
Rename projects.
Rename projects.
Rename projects.
Add tooltip displaying path to current collection.
New screenshot.
Only close the empty tab after the new collection has been opened. Avoid ending up in a situation where nothing is open.