Added API to disable starting advertisement automatically

Added API to disable starting advertisement automatically

And advertisement data can be set just before starting
Following Two Pathces are integrated
1.Added API to disable starting advertisement automatically [Problem] There is no possibility to don't start advertisement.
  It is always started automatically. [Cause & Measure] Advertisement is started automatically in CAStartLEGattServer

2.Advertisement data can be set just before starting
  [Problem] It's not possible to set advertisement data after bluetooth is enabled but before advertising is started.
  [Cause & Measure] current implementation assumes setting advertisement data before turning on BT.
  This feature adds possibility to set function that will be called just before starting advertising

Change-Id: I773bbfc7bb53306609812ec9600d86d29e35d27e
Signed-off-by: Amit KS <amit.s12@samsung.com>