Last commit before bed.

- Make this work per #1344

- Also apply cleanup for #1514

Introduced lcd_strlen() and lcd_strlen_P().
Replaced the old functions where necessary.
Reworked language_ru.h.

Speeded up test for zero length string in cardreader.cpp

- K8200 uses a non-standard RAMPS with Z_ENABLE=63 ??
- Assuming from previous input that 3DRAG is the same.

The `float` keyword should not be on these vars because they conceal
the outer vars, preventing them from obtaining known values before
being passed in `set_bed_level_equation_3pts`. Possibly related to
`Z_RAISE_BETWEEN_PROBING` not functioning.

Fixed how stepper ISR figure it out when the head (extruder) is going to
Min or Max direction.
Added Homing to Max Endstops.

- Naive implementation, assuming the data sheet pin numbers correspond
to Arduino pin numbers.

Fixed delay-times during Init. REPRAP_DISCOUNT_FULL_GRAPHIC_SMART_CONTROLLER won't get initialized on some Boards because delay was to short.

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.

Include of language_en.h now behind national language.

All "#define MSG_STR_*" now surrounded by #ifndef and #endif.

+ May decrease the workload for feature developers. They may omit to
update all the language files but "language_en.h". When loading _en
first, all new features give some display, but the new in English.

- May throw some additional warnings about redefinition during compile.

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.

- Display fan speed 0-1 as “—“ and 254-255 as “100%”.
- Display 4th extruder instead of the heated bed

Example Configuration.h: fixed strange white characters preventing
compilation in lines 1 and 3 - oops

Example Configurations for K8200 readme.md updated
* readme.md: added description for german umlaut support on LCD

Example Configuration_adv.h for K8200 back in sync
* Configuration_adv.h: rebased and added missing changes for 4th
extruder

Example Configuration.h for K8200 back in sync
* Configuration.h: rebased and added missing changes
* Configuration.h: updated comments for K8200

New function now drops the prechar (select character) and makes the first
column usable for text.
Marking the line is now constantly made by highlighting (reverse).

Replaced selection code in:
lcd_implementation_drawmenu_generic()
_drawmenu_setting_edit_generic()
_drawmenu_sd()

with new function.

Combine 1/(rows+1) with u8g.getHeight() to get rowHeight and just use
that.

- Patch from #1453 for delta movement plan
- Fix: Set X with code X instead of adding to X