[SSM] Fix IoT-382, 383 issues

[SSM] Fix IoT-382, 383 issues

1. Fix IoT-382
   -> Tizen ssm sample app crashed when start  with disabling wifi
   : add ip check routine

2. Fix IoT-383
   -> Register query failed when greater than(>) or less than(<)
      operator is used in query using tizen ssm sample app
   : add text unescape function

Change-Id: I1966e122763e31e7b67c0bfded6a8231ed0a401a
Signed-off-by: jk13 <jihyeok13.kim@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/499
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Uze Choi <uzchoi@samsung.com>