• add pico_get_unique_id method to return a unique identifier for a Pico board using the identifier of the external flash
• exposed all 4 pacing timers on the DMA peripheral (previously only 2 were exposed)
• fixed ninja build (i.e. cmake -G ninja .. ; ninja)
• minor other improvements and bug fixes

Additionally, a low level change was made to the way flash binaries start executing after boot_stage2. This was at the request of folks implementing other language runtimes. It is not generally of concern to end users, however it did require a change to the linker scripts so if you have cloned those to make modifications then you need to port across the relevant changes. If you are porting a different language runtime using the SDK boot_stage2 implementations then you should be aware that you should now have a vector table (rather than executable code) - at 0x10000100