Don’t set CUSTOM_M_CODE_SET_Z_PROBE_OFFSET if there’s no Z probe

make it unconditional
remove all definitions in the 'Configuration.h's
remove form 'Conditionals.h'

- Address issue #1669
- Remove the TOPO_ORIGIN configuration setting

- `Conditionals.h` is included twice, setting LCD values the first time

- Add `Conditionals.h` with calculated configuration values
- Add `SanityCheck.h` with checks for configuration errors
- Remove equivalent code from all configurations
- Move error checks from some sources to `SanityCheck.h` also
- Fix initialization of count_direction in stepper.cpp

- Addressing issue #1608

Added option to set Travel Acceleration (non printing moves).
The M204 options was a non sense (S for printing moves and T for retract
moves).

It has been changed to:
P = Printing moves
R = Retract only (no X, Y, Z) moves
T = Travel (non
printing) moves

I will add this info o G-Code wiki in reprap.org. I also advise to put
this info in Marlin next version changelog.

- Moved sanity-checks to Marlin_main.cpp
- Applied to other configuration files
- Fixed formatting of ABL output
- Passing verbose level to probe_pt
- Miscellaneous cleanup
- Put CONFIG_STEPPERS_TOSHIBA into Configuration.h

Looks like INVERT_E3_DIR was missing in the configuration.h also as I
did a test compile with 4 extruders and Azteeg X3 Pro defined. So I also
added those lines too. Additional formatting to make the comments line
up better in that section.

I've insert the define and pointer entries for the Viki 2 and miniViki
from Panucatt in all of the example configs and main config. With these
additions and with pins done in the old single pin.h style...I was able
to get the display working fine save for needing to turn Delta Segments
per Second down. But that's a common graphics lcd issue being looked
into right now.

I need assistance in understanding how the new divided pins files fit
together because my previous attempts at trying to get it to work
appropriately didn't seem successful. This originally came from trying
to find out how to swap the XYZ Min and Max Endstop pins in the Azteeg
X3 Pro. It only comes with one set of connectors and they're Min
Endstops. My previous experience didn't turn out well trying to tell the
firmware to home to the Min Endstops so the best solution I found was to
swap the pins in the firmware. If I'm missing a conflict with a setup
other than delta please let me know, but it makes sense in my setup.

Here were a few changes that I had to make/add lines for the 4th hotend.
A compiling problem in the Temperature.cpp and missing lines in
configuration.h and configuration_adv.h. I added these lines in all of
the example configs too.

Added boards.h which contains defines for all the board numbers, plus
some shorthand macros for less typing.

Added boards.h which contains defines for all the board numbers, plus
some shorthand macros for less typing.

it's caracteristics are :

R25℃ ;100KΩ±1%

B Value(R25/50℃)：3990K 1%
Dissipation Factor(mW/℃)：1.1~1.6 In still Air
Thermal Time Constant(S)：10~17 In Still Air
Operating temperature range：  (-50~+260°C)
Dimension：  1.8mm Dia X4.1mm
Lead Length  ：30mm

This table was found on the following blogs:
http://cae2100.wordpress.com/2014/03/08/beta3950-thermistor-table-for-marlin/

and

http://microfabricator.com/articles/view/id/531ad7e59a/beta-3950-thermistor-table-for-marlin

Add digipot i2c control for MCP4451
Allow M907 to set i2c digipot currents in amps
Fix Makefile to allow Azteeg motherboards
Fix Makefile to allow Wire libraries only
Add beeper pin for Azteeg X3 Pro