Architecture: Semantic meaning of the definition of SAVE_ON_FLASH

:) It's what gets set when you're building for devices with very little flash memory - so it does things like:

• doesn't include non-vital JS functions and classes (I think waveform gets ripped out for instance)
  
• doesn't inline some functions (would have been done for speed, but saves space if they're not inlined)
  
  

... but it doesn't have anything to do with saved program code at all.

Not sure where the best place is to document it is actually - maybe we could add something to README_BuildProcess.md?