#1 LibraryMemory error

[Gregor Brunmar]

Repeat bug:
------------
1. Open project
2. Close project
3. Open project -> Generates NullPointerException in
memory.LibraryMemory.memorize():42

Cause:
-------
LibraryMemory creates the Vector libraries as a static
variable. LibraryMemory.dispose() is then called when a
project is closed and sets LibraryMemory.library to
null. Then when a new project is opened again, the
LibraryMemory.library is still null.