Fixed System Tick timer usage. Timer is only 24 bit!
Fix stack pointer corruption hard fault when running with gdb, simplify test file to not require the timer, and disable adding build-id when linking (the linker puts this in the same place as the reset handler.
Remove message referring to multiple branches
Fix for building on OSX

Some of these settings need to move to a non-version controlled config
file.
Fixes for non-GNU tail and sed, plus a few OSX-specific fixes