[Workflow] Added simple sublime project config file.
[Doc] Added tips and tricks section to the HACKING document.
Add preliminary support for STM32F0 branch Cortex-M0

Supported modules:

MEMORYMAP
IRQ (untested)
RCC
GPIO
FLASH (untested)
PWR (untested)
CRC (untested)
M0 core (partially tested)

TODO:
* Some files needs fixes, some common files from cm0 and cm3 are same and needs to be grouped.
* GPIO is same as in F24, common gpio file needs to be renamed to gpio_common_f024 (undone due
to merge this change with F3 compatibility too)
cm0: fix CPUID-offset
cm0: SHCSR and DFSR are only accessible from DAP
cm0: remove non-existent MPU areas for core < M0+ (based on Florian Larysch pull request)
Merge branch 'F0-compat' of ssh://github.com/BuFran/libopencm3 into F0-compat