Fix insert-heading

* lisp/org.el (org-insert-heading): Fix problem with inserting
  heading.

The commit fixes a bug introduced in bb2022.
ox-koma-letter: Use same hotkeys as LaTeX export

  * ox-koma-letter.el (koma-letter): Use `L' to export to LaTeX
  buffer, `l' to export to LaTeX file, and `o' to export to PDF
  file and open.

Patch suggested by Rasmus.

Signed-off-by: Alan Schmitt <alan.schmitt@polytechnique.org>
ox-koma-letter.el: Set LCO option before other KOMA variables

  * ox-koma-letter.el (org-koma-letter-closing): More
  business-like closing.
  (org-koma-letter-from-address): Do not set default personal
  information.
  (org-koma-letter-opening): Gendered opening.
  (org-koma-letter-phone-number): Do not set default personal
  information.
  (org-koma-letter-sender): Use `#+SENDER:' instead of
  `#+AUTHOR:' because the latter is always set by the LaTeX
  exporter.
  (org-koma-letter-email): Duplicte `#+EMAIL:' in this exporter
  because it is always set by the LaTeX exporter.
  (koma-letter): Add additional `#+SENDER:' and `#+EMAIL:' to
  exporter (see above).
  (org-koma-letter-template): Set LCO before evaluating other
  KOMA variables if they are set; add `#+SENDER:' and `#+EMAIL:'
  to template (see above).

The LCO file is set loaded first and KOMA variables are only set if
their value is not `nil'.

Example:

  #+LCO: Default
  #+SIGNATURE: A friend

will result in the following LaTeX code:

  #+BEGIN_SRC latex
  \LoadLetterOption{Default}        % LCO file, with default signature
  \setkomavar{signature}{A friend}  % Overwrite signature
  #+END_SRC

Other KOMA variables defined in the LCO file, e.g., `fromaddress', will
not be overwritten.

Signed-off-by: Alan Schmitt <alan.schmitt@polytechnique.org>
ox-koma-letter: Export options to control letter

  * ox-koma-letter.el ((org-koma-letter-use-subject):
  Configure printing of subject line.
  (org-koma-letter-use-backaddress): Configure presence of back
  address.
  (org-koma-letter-use-foldmarks): Configure presence of foldmarks.
  (org-koma-letter-use-phone): Configure printing of phone number.
  (org-koma-letter-use-email): Configure printing of email.
  (org-koma-letter-use-place): Configure printing of place.
  (koma-letter): Add export option to exporter backend.
  (org-koma-letter-template): Evaluate export options in
  exporter template.

Usage:

  #+OPTIONS: backaddress:t foldmarks:t subject:titled phone:t email:t place:t

Except for `subject', all options are boolean, i.e., the accept the
values `nil' and `t'. `subject' accepts the values defined in
`scrlttr2`, i.e., `afteropening', `beforeopening', `centered', `left',
`right', `titled', `underlined', and `untitled'.

Signed-off-by: Alan Schmitt <alan.schmitt@polytechnique.org>
ox-koma-letter.el: Support multiple LCO files

  * ox-koma-letter.el (org-koma-letter-template): Treat `#+LCO:'
  variable as a list of multiple LCO files separated by spaces.

Example:

  #+LCO: Default Signed

will result in the following LaTeX fragment

  #+BEGIN_SRC latex
  \LoadLetterOption{Default}
  \LoadLetterOption{Signed}
  #+END_SRC

Signed-off-by: Alan Schmitt <alan.schmitt@polytechnique.org>
ox-taskjuggler.el: Add a command to process and open an exported file for tj3

* ox-taskjuggler.el (org-taskjuggler-process-command)
(org-taskjuggler-reports-directory): Add a defcustom to define
the tj3 command and the directory where the reports are to be
generated.
(org-taskjuggler-export-and-process)
(org-taskjuggler-export-process-and-open): Split the command
so that you can now process and open in separate commands.
(org-taskjuggler-compile): New function to process a tjp file
using org-taskjuggler-process-command.

Finally we have support for processing and opening the exported file
with tj3.  For TaskJuggler 2.4 this always worked. Now it also works
for tj3.  `org-taskjuggler-export-and-process' exports the file and
runs it through tj3.  `org-taskjuggler-export-process-and-open'
additionally opens the reports in a browser.
ox-taskjuggler.el: Add a TODO to support org-export-with-planning

* ox-taskjuggler.el: Add a TODO to support org-export-with-planning.
ox-texinfo: Default to buffer-file-coding-system when exporting

* lisp/ox-texinfo.el (org-texinfo-coding-system): Clarify default
  setting.
  (org-texinfo-template): Ensure buffer-file-coding-system is used
  when org-texinfo-coding-system is not set.