Fix NRF51822 PWM and Serial:
- imlement pwmout_free()
- check UART interrupt type carefully
- implement serial_set_flow_control()
- add serial_clear() stub
[NUCLEO_F091RC] First commit of HAL files
[NUCLEO_F091RC] Update python files for this target, add uVision exporter
[NUCLEO_F091RC] First commit of CMSIS files
Merge pull request #535 from bcostm/dev_F091RC

Platform: New platform addition - NUCLEO_F091RC
[DISCO_F429ZI] missing interrupt vectors

Added some missing F429 interrupt vectors
[DISC_F407VG & ARCH_MAX] change default toolchain
[NUCLEO_F091RC] pin_mode for Serial only if the pin is present

Same as all other targets.
Merge pull request #538 from bcostm/master

HAL: NUCLEO_F091RC - pin_mode for Serial only if the pin is present
[HAL][ARCH_MAX] use different PeripheralNames.h for STDIO_UART
Merge pull request #537 from xiongyihui/stm32f407

HAL: DISC_F407VG, ARCH_MAX - change default toolchain

- ARCH_MAX - use different PeriheralNames.h files
[DISCO_F429ZZI] pin function definition

Added mostly all pin function (ADC, I2C, SPI, UART, PWM).

The basis of the target was DISCO_F407. The 429 has some additional pin
functions which are added with this commit. Also ports, pins and pin
functions of the larger packages are added not only the available of the
F429ZI package.
[NUCLEO_F030R8] port HAL to support cube and ad cube files as well
Merge pull request #541 from dbestm/master

HAL: NUCLEO_F030R8 - port HAL to support Cube and cube files addition
Merge pull request #534 from anpilog/master

HAL: nrf51822 - Few fixes for PWM and Serial
[NUCLEO_F401RE] enhance gcc ld file
Merge pull request #543 from dbestm/master

CMSIS: NUCLEO_F401RE - ARM GCC ld RAM size correction
[DISCO_F429ZI] changed mcu names

Changed mcu names in comments from original F407 ot F429.
[README.md] some changes and additions

Changed web addresses from mbed.org to developer.mbed.org, added some
Nucleo and one Discovery board, reorder of the Nucleo boards depending
on M0, M3, M4.
[README.md] some more changes and additions

Some more web addresses changes and added CoIDE as toolchain.