Separated main and wiring, wiring builds as a library (WIP-linking fails)
Merged in latest feature/hal branch (running make in main/build fails)
Code cleanup - removed obsolete SPARK_XXX_ENABLE macros and related code
WIP : main build error (code compiles but linking fails)
removed unused code from wiring makefile. changing the order of the libs declared in main fixes the build, need to find out why!
fix for interrupts from stm32_it.c being discarded by linker.  It seems the linker discards them because it is preferring the weak symbols from the startup .S asm file. By adding a string symbol to stm32_it.c, the object file is kept by the librarian and the ISRs properly overridden.
Merge branch 'feature/hal-wip' into feature/hal