Addition of missing strings to match language_en.h

Small corrections

Added tarnslation for
```
#define MSG_DEBUG_MENU 
#define MSG_PROGRESS_BAR_TEST
```

- Japanese and Chinese still need update

Add symbol-string for _de
to reduce the frquencey of regenerating 'mappers' and 'fonts'
with the new utf-system.

#define MSG_ENDSTOP_ABORT  doesn't fit in Display 
See https://github.com/MarlinFirmware/Marlin/issues/5401#issuecomment-265714487

Grammar corrections

Made Filament change Text sound like correct german.

Change some string to get a better wording in german

@MarlinFirmware/language-team updated german languagefile to the latest english version

MSG_MOVE_E1 was missing
MSG_MOVE_E2 was missing
MSG_MOVE_E3 was missing
MSG_MOVE_E4 was missing

I assigned "0" to "MSG_MOVE_E1", "1" to "MSG_MOVE_E2" and so on, as this is what i assume to be the standard naming for the first (E0) and second (E1) extruder. This would have to be changed inthe other languages too :(

Added german translation for MSG_INFO_PRINT_LONGEST and  MSG_INFO_PRINT_FILAMENT.
MSG_HEATING_COMPLETE changed from "Aufgeheizt" to "Extr. aufgeheizt"
MSG_HEATING changed from "Aufheizen" to "Extr. aufheizen"

・Remove MSG_END_HOUR and MSG_END_MINUTE from all the language files
・Change from MSG_INFO_TOTAL_PRINTS to MSG_INFO_PRINT_COUNT in German
file

@MarlinFirmware/language-team my changes for the German language. Feel free to improve :)

There is no way to translate "A-travel" to "A Rückzug". Thats simply
wrong.

We don't have to  avoid German "Umlaute" any more.

In all these cases we want the axis to be homed. If we could have lost
some steps is secondary.

Reenables homing seperate axis with DISABLE_X / DISABLE_Y true.

Following up on #3231

documentation/LCDLanguageFont.md moved to http://www.marlinfirmware.org/ at commit 12d0983757,
but http://www.marlinfirmware.org/ isn't working.

Keep "astyled" reformatting

Apply `ENABLED` / `DISABLED` macros to language-related files.

and translate them to German.