This is useful to launch from a terminal without "blocking" this terminal.
There are tools like nohup and daemonize (BSD) to do the same, but having it
builtin is shorter to write.

* Other editors call "backup files" previous copies of saved files.
  This role would be served by savepoint files in SciTECO.
* Likewise filename~ would point to such a backup file.
  It therefore makes sense that savepoint files also end in tildes (.teco-n-filename~).
* Security copies of modified buffers would be called "auto-saves" (Emacs) or
  "swap files" (Vim).
  Both of these terms is IMHO misleading, so SciTECO now uses the
  term "recovery file".
* "Recovery files" are now named #filename# just like in Emacs.

* The backup mechanism is supposed to guard against crashes of SciTECO and
  unexpected program terminations (e.g. power cycling, etc.)
* In a given interval (no matter whether busy or idlying on the prompt)
  SciTECO saves all modified buffers with the filename~ (like most other editors).
  As an optimization files are not backed up if they have been backed up
  previously to avoid pointless and possibly slow file system writes.
* While the backup mechanism exists outside of the usual undo-paradigm -
  backup file creating is not bound to character input and it makes no sense
  to restore the exact state of backup files - there are some interesting
  interactions:
  * When a buffer is dirtyfied or saved that was previously backed up, it must always
    be reset to the DIRTY state on rubout, so backups are eventually recreated.
  * When a buffer is dirtyfied first (was clean), the backup file must be
    removed on rubout as well - we don't expect backup files for clean buffers.
* There is currently no automatic way to restore backup files.
  This could potentially be done by opener.tes and session.tes in the future,
  although you couldn't currently always get meaningful user feedback
  (whether he wants to restore the file).
  Perhaps we should at least log a message when detecting backup files that
  are newer than the file that is being opened.

* This currently needs a yet unmerged patch, fixing the light colors.
* Scinterm no longer systematically initializes the color pairs, so
  we cannot predict their numbers - instead we initialize color pairs
  on demand and store them in a hash map, very similar to what Scinterm
  does internally.
* Scinterm v5.5 can use arbitrary RGB colors now by automatically
  allocating curses colors and pairs.
  We do not expose this in SciTECO yet, although that would also
  be possible.
  It has to be decided first whether the special predefined colors
  will continue to live in the same namespace along with "true"
  RGB colors.

* When typing nEBfilename$ (n != 0) you would find out that the construct is invalid
  only after typing out the entire command.
  We now throw an error immediately, ie. only Escape or string termination will be expected
  in interactive mode.
* In batch mode, nothing should have changed.

* The Knowledge Base replaces the Github wiki.
* The mailing lists replace the Github bug tracker, discussions and pull requests.