Re-run issue analysis when issue options are changed.
Use different error message when debugger is used in 64-bit process.
Re-run issue analysis when LoadSolutionProjectThread finishes.
GotoDialog and CodeCompletion-window: Fix window being closed when double-clicking the list's scroll bar.
Fix performance problem with DerivedTypesTreeNode.

Once the DerivedTypesTreeNode was created, any change to the type definition was causing an expensive search for derived types; even if the DerivedTypesTreeNode was collapsed.
We now never perform this search on updates, and instead collapse the node.
Don't use ModelCollectionTreeNode for class browser nodes that don't use a IModelCollection.
Don't throw NotImplementedExceptions in IParser.ResolveSnippet() - see #399