Enabled heap_and_stack test for baremetal.
Added a test to check that global variables are initialised.
In mbed_sdk_boot:
- Added initialisation for mbed_stack_isr_start/size and mbed_heap_start/size for all toolchains.
- ARM toolchain:
- Added call to mbed_toolchain_init() to initialise global variables.
- Moved microlib initialisation code from mbed_retarget.cpp to mbed_sdk_boot.c.
- IAR toolchain: there is no equivalent to a software init hook that can be called. __low_level_init() was used but since this function is called before RAM initialisation, it cannot be used to initialize global variables. Defined a new __mbed_init() function called from IAR startup file instead.
Added missing mbed_error_initialize function call in bare metal boot code which is used
to retrieve the crash report from RAM in case of any previous abnormal re-boot but this function call is present in RTOS boot code.
Also includes:
* rename `mbed_sleep_manager.c` to `mbed_power_mgmt.c` to match its
header file
* create Doxygen groups for public and internal APIs
* use relative path to include header files where inconsistent
* update references to internal APIs throughout libraries
* update the copyright year for all modified files
Evelyne Donnaes
Rajkumar Kanagaraj
Hugues Kamba