refactor(gtd): move OpenCortex tasks to project-local TODO.org

- Slim gtd.org by linking to projects/opencortex/TODO.org
- gtd.org reduced from 1615 to 822 lines (-793)
- OpenCortex tasks now live in projects/opencortex/TODO.org
- Add projects/opencortex/TODO.org to org-agenda-files

Engineering Core and personal tasks remain in gtd.org

projects/dotemacs/modules/emacs-gtd.org

@@ -15,10 +15,11 @@ Basic agenda settings
 Agenda files
 #+begin_src elisp
   (setq org-agenda-files (list
-  			(concat org-directory "/inbox.org")
-  			(concat org-directory "/gtd.org")
-  			(concat org-directory "/org-gtd-tasks.org")
-  			)
+			(concat org-directory "/inbox.org")
+			(concat org-directory "/gtd.org")
+			(concat org-directory "/org-gtd-tasks.org")
+			(concat org-directory "/projects/opencortex/TODO.org")
+			)
         )
 
 #+end_src