WINTERMUTE: Introduce Wintermute::Error class instead of single bytes;

Simplify error handling, prune enums, remove the useless printError(Error) function;
printError() is, for all purpouses, superseded by getErrorDisplayStr().
Fix behavior of RemoveBreakpoint, add getTypeStr() to ScValue
Fix sourcePath-not-null check in printSource
WINTERMUTE: Fix whitespaces in error messages