Move `/includes` to `/rts/include`, sort per package better

In order to make the packages in this repo "reinstallable", we need to
associate source code with a specific packages. Having a top level
`/includes` dir that mixes concerns (which packages' includes?) gets in
the way of this.

To start, I have moved everything to `rts/`, which is mostly correct.
There are a few things however that really don't belong in the rts (like
the generated constants haskell type, `CodeGen.Platform.h`). Those
needed to be manually adjusted.

Things of note:

 - No symlinking for sake of windows, so we hard-link at configure time.

 - `CodeGen.Platform.h` no longer as `.hs` extension (in addition to
   being moved to `compiler/`) so as not to confuse anyone, since it is
   next to Haskell files.

 - Blanket `-Iincludes` is gone in both build systems, include paths now
   more strictly respect per-package dependencies.

 - `deriveConstants` has been taught to not require a `--target-os` flag
   when generating the platform-agnostic Haskell type. Make takes
   advantage of this, but Hadrian has yet to.

1 files changed, 4 insertions, 4 deletions

diff --git a/CODEOWNERS b/CODEOWNERS
index c1429a0ded..4f71e6464a 100644
--- a/CODEOWNERS
+++ b/CODEOWNERS
@@ -13,13 +13,13 @@
 [RTS-like things]
 /rts/                             @bgamari @simonmar @osa1 @Phyx @angerman
 /rts/linker/                      @angerman @Phyx @simonmar
-/includes/                        @bgamari @simonmar @osa1
+/rts/include/                     @bgamari @simonmar @osa1
 
 [RTS heap profiling]
 /docs/users_guide/profiling.rst   @DanielG
-/includes/rts/ProfHeap.h          @DanielG
-/includes/rts/TraverseHeap.h      @DanielG
-/includes/rts/storage/ClosureMacros.h @DanielG
+/rts/include/rts/ProfHeap.h        @DanielG
+/rts/include/rts/TraverseHeap.h    @DanielG
+/rts/include/rts/storage/ClosureMacros.h @DanielG
 /rts/LdvProfile*                  @DanielG
 /rts/ProfHeap*                    @DanielG
 /rts/Retainer*                    @DanielG