As noted by @FalloutBe in #3519

・Add more "UL" suffix
・Restore removed "UL" suffix

Only measure and store filament width when E is going forward.

Following up on #3231

Fixes for #3189

Setting a temp is still missing

Adds the parameter U to M303. If U1 is included , it will use the
PID-values from the auto-tune.

Addition to #3140

Addressing #3085. If the target_temperature is set directly it never invokes or disables the timer set in `start_watching_heater`, so after _stopping a print_ or turning off _all heaters_ you could get a “Heating failed” error.

Apply `constrain`, `NOMORE`, `NOLESS` and `CRITICAL_SECTION` macros
wherever possible.

Based on #2860 - rebased for RCBugFix

Make the output of M105 more similar to Repetier.
Make the text-print pert of M105 an extra function to make it reusable. `print_heaterstates()`
Use `print_heaterstates()` in M019, M190 and M303

in language.h, but was not renamed here. If TEMP_SENSOR_1 is enabled as redundant then
an error is thrown that MSG_EXTRUDER_SWITCHED_OFF is not defined.

Originaly by @12dstring

Keep "astyled" reformatting

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

instead of 1000.  Else we get errors with times over 32 seconds.

Also clean up some trailing spaces in a few other sources

Fixes the problem of these pins being left in INPUT state, as described
in #1497

Now send only temperature for T or B, but not send OK.
Host interprets the line to show the right temperature, but not in
response to M105 then stop and send commands until it ends the autotune.

If the target temperature is changed then it would always stay in the reset state.
Thanks to @tonokip.

Replaces #2119