Rename vg_preload_core.so to vgpreload_core.so to be consistent with
tool preload modules, which are called vgpreload_<tool>.so.  Also
fixed a couple of comments relating to this.

(This need not be merged into 3_0_X.)


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@4514 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/include/pub_tool_redir.h b/include/pub_tool_redir.h
index 8a65715..2e657ed 100644
--- a/include/pub_tool_redir.h
+++ b/include/pub_tool_redir.h
@@ -64,7 +64,8 @@
 
    Note also that the replacement function should probably (must be?) in
    client space, so it runs on the simulated CPU.  So it must be in
-   either vg_preload_<tool>.so or vg_preload_core.so.
+   either vgpreload_<tool>.so or vgpreload_core.so.  It also only works
+   with functions in shared objects, I think.
    
    It is important that the Z-encoded soname contains no unencoded 
    underscores, since the intercept-handlers in vg_symtab2.c detect