Work in progress.

- Got rid of vectors of vectors in generators code. That was not only slow, it
  was also troublesome.
- Started work on transformation caching. Works but needs review/cleanup.


[SVN r15465]

tools/build

@@ -1 +1 @@
-Subproject commit 660fa0a58120d0f5ba86d06b510e8afc82dc60b3
+Subproject commit 38f178b0d82959a961a525585c734186d92865d5