Make OctoPrint happily draw temperature curve while waiting for heating

[thomaskilian]

I'm using OctoPrint and found that while waiting for the bed/ext to heat up it got no temperature feedback. So instead of just posting "Waiting...." there's now the current temperature echoed.

[Wurstnase]

Maybe you could send a M155 S1 to report the temperature every second before waiting for reaching the temperature. I've never test this.

[phord]

Periodic temperature reporting with M155 is added on the experimental branch at 47dfcf1a44d8fad4edac2b23cb894f98b961365c.

[thomaskilian]

Well, I tested my change on OctoPrint and it was happy to read the temperature log line rather than "Waiting..." to continuously show the temperature graph. Didn't look like a ground breaking and every thing changing modification.

[phord]

Dup of 47dfcf1