org.el: Use normalized names in org-agenda-file-p

* lisp/org.el (org-agenda-file-p): Make sure all filenames are
normalized before performing comparison.
org.el: Fix bindings of < and > for calendar scrolling

* lisp/org.el (org-read-date-minibuffer-local-map): Switch to the
  current calendar API for scrolling the calendar.
ORG-NEWS: Document new options
Merge branch 'maint'