add create_threshold function

Move threshold logic into a seperate function for later changes.

Change-Id: I9dadb014ee42fc19ba686413dfa2c0da70f2582f
Signed-off-by: Rashmica Gupta <rashmica.g@gmail.com>
diff --git a/virtualSensor.hpp b/virtualSensor.hpp
index 71a66ca..6107fa1 100644
--- a/virtualSensor.hpp
+++ b/virtualSensor.hpp
@@ -132,6 +132,9 @@
     void initVirtualSensor(const Json& sensorConfig,
                            const std::string& objPath);
 
+    /** @brief create threshold objects from json config */
+    void createThresholds(const Json& threshold, const std::string& objPath);
+
     /** @brief Check Sensor threshold and update alarm and log */
     template <typename V, typename T>
     void checkThresholds(V value, T& threshold)