Merge changes I96d1ccad,I1c13fe1e,I941a8988,I94ec870b,I81f45816, ... into tizen_2.4
* changes:
[SAMPLE APP][Bluetooth LE Collector] Device's discovery section updated
[SAMPLE APP][Bluetooth LE Collector] Application's model section added
[SAMPLE APP][Bluetooth LE Collector] Discovered device's service data acquisition section added
[SAMPLE APP][Bluetooth LE Collector] 'Devices discovery' and 'Discovered device's details acquisition' sections restructured
[SAMPLE APP][Bluetooth LE Collector] Discovered device's details acquisition and browsing
[SAMPLE APP][Bluetooth LE Collector] Devices discovery section added
[SAMPLE APP][Bluetooth LE Collector] Initialization section added
[SAMPLE APP][Bluetooth LE Collector] Application's workflow added
[SAMPLE APP][Bluetooth LE Collector] Images alt desc added
[SAMPLE APP][Bluetooth LE Collector] Overview section added
[SAMPLE APP][Bluetooth LE Service] References section added