reorganize into core plus packages

The "racket" directory contains a pared-back version of the
repository, roughly.

The "pkgs" directory everything else in the repository, but
organized into packages.

original commit: b2ebb0a28bf8136e75cd98316c22fe54c30eacb2

pkgs/profile-pkgs/profile-doc/info.rkt

@@ -0,0 +1,4 @@
+#lang setup/infotab
+
+(define build-deps '("profile-lib"
+                     "racket-doc"))

pkgs/profile-pkgs/profile-lib/info.rkt

@@ -1,2 +1 @@
 #lang setup/infotab
-

pkgs/profile-pkgs/profile/info.rkt

@@ -0,0 +1,4 @@
+#lang setup/infotab
+
+(define deps '("profile-lib"
+               "profile-doc"))