no files found ./target/thumbv7m-none-eabi/debug/deps/app-*.o

There were files without a `.o` suffix containing symbos (reset handler and RESET_VECTOR symbol).  I'm not sure if this is what the documentation intended to show, but if so, I am on rust 1.32.0, so this may have changed?.  Documentation updated as per #39.

Note contents of  `#include ../ci/smallest-no-std/app.o.nm` shows rust_begin_unwind` differ from above.

