GXemul Code2

unit tests, etc.
The ActionStack now uses lists instead of vectors, for the
undo and redo stack. (For O(1) undo/redo operations.)
Continuing on the Component infrastructure: parent/child
relationships, state variables, and serialization.
Adding a simple Checksum class; useful as a helper for unit
tests.
20071228 Implementing a CreateComponent function, which when given a
"component class name" creates a Component.
Adding a simple EscapedString helper class, for generating and
decoding C-style escaped strings.
Simple deserialization works. :)