Methods for Cortex-M processors to determine stack size and how much of the stack has been or is being used.
Warning: this crate depends on the _stack_start and _stack_end symbols being set correctly.
The cortex-m crates achieve this with their linker scripts, but the flip-link linker does not until PR #126 has landed.
Use [current_stack_in_use] or [current_stack_free] to keep track of the memory usage at run-time.
First paint the stack using [repaint_stack] and then measure using [stack_painted] or [stack_painted_binary] to figure out how much stack was used between these two points.