Fix temperature checking conditions (backwards!)

Update U8glib URL

M104 not starting the print timer

Echo all debug levels in M111, default to DEBUG_NONE

Redo of #3268 by @jbrazio

Refinements, fixes, reduced stack usage in CardReader

M190 bed temp is never reached

Minor cleanup to filament sensor code

Keep blinking limited to LCD_UPDATE_INTERVAL

Cleanup, simplification of command dispatcher code

Relax the test for "Heating failed" errors

Formatted multi-line comments

Use SBI macro

Fix typo

Make the Autotune option(s) in the LCD menu optional

Host Keepalive: Reduce frequency of "busy" messages

Update Japanese translation

Fixed backlight for PCF8575.

Fix: current_command_args skips digits at the front

These are salvaged from closed-PR #3216.