Add argument `action` as first positional argument, the second
positonal argument is for tests.
Add actions `doc` and `config`, doc works on org files and config works
on configuration file like packages.el.
The special action `all` performs all actions.
Move test files to `test` sub-folder.
Choose between `md5sum` and `md5` (on OS X) executables.
Add a new formatting function `move-packages-to-config` to move
package lists to config.el file.
Add test mode: {repo-root}/core/tools/doc-fmt/run.bash test
applies formatting only to {repo-root}/core/tools/doc-fmt/test.org
Use "gsed" if present.
Add new filters, refactor code.
test.org now represents most of the .org file formatting errors.