Currently we use the probe exclusively as a device to find the build platform(bed).
For the currently supported setups this means, we use it as a additional min-endstop.
A triggered when not deployed probe disturbs the homing process for max-endstops.

Rename ENDSTOPPULLUP_ZPROBE to ENDSTOPPULLUP_ZMIN_PROBE
Rename Z_PROBE_ENDSTOP_INVERTING to Z_MIN_PROBE_ENDSTOP_INVERTING
Rename Z_PROBE_ENDSTOP to Z_MIN_PROBE_ENDSTOP
Rename DISABLE_Z_PROBE_ENDSTOP to DISABLE_Z_MIN_PROBE_ENDSTOP
Rename Z_PROBE_REPEATABILITY_TEST to Z_MIN_PROBE_REPEATABILITY_TEST
Rename Z_PROBE_ENDSTOP to Z_MIN_PROBE_ENDSTOP
Adjust comments accordingly
Remove Z_MAX  check for the probe in update_endstops().

Using an delta related idea of @clefranc from #61,
extended to the general change for all setups.

Tested with Prusa i3, max-z-endstop and permanently triggered z-probe.
Worked for @clefranc's delta.

Now all ramps configuration can enable Filament sensor not only EEB

If the printer is going to accept the M999,
then it should continue from that line number.

only X and Y were not implemented

PR#2572 Changed this because of faulty Boolean Logic

NOT(A OR (NOT B) OR (NOT C)) !=

(NOT A) AND ((NOT B) OR C))


Besides, the compiler should be smart enough to
optimize this without help from the programmer

**** NOTE ****
This code is very EXPERIMENTAL and UNSUPPORTED

See http://platformio.org/

Provide both long and short version strings

The long descriptor will still be available in M115

Centred the logo for 16x4 and 20 x4.
Moved version to the bottom line
Code shrink to 704 bytes.

Saves about 473 byte of progmem and 28 bytes of RAM.

Uses about 488 byte of progmem and 32 byte of RAM.
For that configurable.

- For some reason it’s easy to forget what BT stands for, but it
doesn’t need an abbreviation.

- The default serial baud rate of 115200
- The regular RigitBot bed size 254mm/248mm/254mm
- Single stock extruder
- Stock termistors for extruder and hotbed
- Stock Min X/Y/Z stops. Max stops not connected
- Stock 32 teth tooleys (stock axis steps)
- No auto bed leveling
- No screen