hotplug: call handle_device.d/ actions for remove

* Original actions didn't care about remove (10-span-types, 20-span-assignments)
* But others need to know about removals too.

Signed-off-by: Tzafrir Cohen <tzafrir.cohen@xorcom.com>
Acked-by: Russ Meyerriecks <rmeyerriecks@digium.com>
registration-order: Added dahdi_auto_assign_compat

Maintains the original registration order as was before span
assignments. Should allow seemless trannsition to
dahdi.auto_assign_spans=0

* The idea:
  - We stop handling in udev the case of missing
    /etc/dahdi/assigned-spans.conf
  - Instead we rely on "registration_time" dahdi_device attribute from
    DAHDI-linux
  - Then, we can sort the devices and assign their spans in
    /etc/init.d/dahdi
* Mechanics:
  - From /etc/init.d/dahdi, we run a new 'dahdi_auto_assign_compat'
    script (after "waitfor_xpds" etc.)
  - In this script we "auto" assign spans of non-Astribank devices
  - In the end of the script we run "dahdi_registration" which
    does the same for Astribank devices.

Signed-off-by: Tzafrir Cohen <tzafrir.cohen@xorcom.com>
Acked-by: Russ Meyerriecks <rmeyerriecks@digium.com>
improved dahdi_span_types dumpconfig

* Better defaults:
  - A wildcard match:
    - If '--line-mode' option is given, generate a wildcard entry.
      (existing behavior).

    - Otherwise, if *all spans* are of the same type (E1/T1),
      generate a wildcard entry for this type.
      This is the most common use-case and now it work without
      any command line flags.

    - Otherwise (mixed E1/T1 spans), do not generate a wildcard entry.
      This isn't common case (except from our labs), but regardless
      without '--line-mode' any guess could be wrong.

  - Specific device matches:
    - If all spans are of the same type, generate commented out
      specific entries (for manual overrides).

    - If spans have mixed E1/T1 types, generate specific entries
      In this case, specific entries MUST NOT be commented out
      otherwise, the configuration file is wrong!

* Generated header with better organization:
  - Shows what is generated:
    - Generating wildcard / Not generating wildcard
    - Generating specific lines / Generating *commented-out* specific lines

  - For each decision, show *why* it was taken.

Signed-off-by: Tzafrir Cohen <tzafrir.cohen@xorcom.com>
Acked-by: Russ Meyerriecks <rmeyerriecks@digium.com>