log: Fix number of parameters of APP_UART_INIT() macro
ll: Add ll_set_advertising_data() API
ll: Add ll_set_scan_response_data() API
bci: Add bci_set_scan_response_data() API
platform/nrf51822/log: Improve buffer length calculation
log: Add volatile modifier

Inform the compiler that the variable can be modified at any time externally
to the implementation, for example, by the operating system, by other thread
such as an interrupt routine or signal handler, or by hardware.
log: Minor code cleanup
log: Add aligned modifier

Use the maximum alignment for a scalar data type.
radio: Add volatile modifier to "status"
build: Add -O2 flag
bci: Fix build warning

stack/bci.c: In function 'bci_set_advertise_enable':
stack/bci.c:145:2: error: 'type' may be used uninitialized in this
function [-Werror=maybe-uninitialized]
cc1: all warnings being treated as errors
ll: Add comments for advertising header
example: Fix length field of broadcaster example
radio: Force alignment

Force maximum alignment for a scalar data type in order to have a better
efficiency when handling memory/data copy.
radio: Use macro instead of magic number

This commit doesn't change the logic. It is replacing a "magic" number by
a constant defined in the NRF51 sdk.
radio: Minor coding style change
radio: Fix NRF PCNF0 config

In-RAM representation of radio packet, S0, LENGTH, and S1 are optional.
For BTLE radio packet, S1 can be omitted setting its length to zero
(omitting in memory).
radio: Remove unneeded buffer copy

memcpy should be avoided at all. Buffer address can be assigned directly
to NRF_RADIO->PACKETPTR register.

This way, we need to provide non-const buffers because Radio EasyDMA
requires an address in the RAM.