ox-odt: Implement `org-odt-format-{headline, inlinetask}-default-function'
* lisp/ox-odt.el (org-odt-format-headline-function): Set this to
`org-odt-format-headline-default-function'.
(org-odt-format-headline-default-function): New. Based on
`org-odt-format-headline'.
(org-odt-format-headline): Remove it.
(org-odt-format-toc-headline): Change signature.
(org-odt-format-headline--wrap): Change signature. Propagate
above changes.
(org-odt-format-inlinetask-function): Set this to
`org-odt-format-inlinetask-default-function'.
(org-odt-inlinetask): Use `:odt-format-inlinetask-function'.
(org-odt-format-inlinetask-default-function): New. Factored out
from `org-odt-inlinetask'.
Port more of
3c22bb19e025e350ebcc25c6fc23e2dd59e49693.