Added modules cmd.Compile and dil.ModuleManager. Added options -I, -release and -unittest to the compile command. Tidied main.d up a bit. Renamed start() methods of SemanticPass1 and 2 to run(). Moved function findModuleFilePath() to class ModuleManager. Added msg CouldntLoadModule. Corrected two others. Added member semanticPass to class Module. Implemented visit(ImportDeclaration) in SemanticPass1.

--- a/src/cmd/DDoc.d	Sun Mar 09 16:39:46 2008 +0100
+++ b/src/cmd/DDoc.d	Tue Mar 11 02:48:01 2008 +0100
@@ -75,7 +75,7 @@
 
       // Start semantic analysis.
       auto pass1 = new SemanticPass1(mod, context);
-      pass1.start();
+      pass1.run();
 
       // Build destination file path.
       auto destPath = new FilePath(destDirPath);