Fix TODO keywords case sensitivity
* lisp/org.el (org-todo-regexp):
(org-not-done-regexp):
(org-not-done-heading-regexp):
(org-todo-line-regexp):
(org-complex-heading-regexp): Improve docstrings.
(org-insert-todo-heading):
(org-fix-position-after-promote):
(org-link-search):
(org-block-todo-from-children-or-siblings-or-parent):
(org-get-todo-state):
(org-priority):
(org-point-at-end-of-empty-headline):
* lisp/org-agenda.el (org-fix-agenda-info):
(org-agenda-get-todos):
(org-cmp-alpha):
* lisp/org-archive.el (org-archive-subtree):
(org-archive-all-done):
* lisp/org-list.el (org-toggle-item):
* lisp/org-pcomplete.el (pcomplete/org-mode/searchhead): Bind
`case-fold-search' to nil when matching aginst one of the regexp
above.
* testing/lisp/test-org.el (test-org/fuzzy-links): Add tests.