Secure ReadProperty decoding and BACnetActionCommand (#702)

* Refactored and secured BACnetActionCommand codec into bacaction.c module for command object and added to bacapp module encode/decode with define for enabling and pseudo application tag for internal use.

* Simplified bacapp_data_len() and moved into bacdcode module as bacnet_enclosed_data_len() function.

* Secured ReadProperty-REQUEST and -ACK decoding.

* Removed deprecated Keylist_Key() functions from usage.

* Removed pseudo application datatypes from bacapp_data_decode() which only uses primitive application tag encoded values.

* Defined INT_MAX when it is not already defined by compiler or libc.

* Deprecated bacapp_decode_application_data_len() and bacapp_decode_context_data_len() as they are no longer used in any code in the library.

* Added BACnetScale to bacapp module. Improved complex property value decoding. Refactored bacapp_decode_known_property() function.

* Refactored and improved the bacapp_snprintf() function for printing EPICS.

* Fixed Lighting Output WriteProperty to handle known property decoding.

src/bacnet/basic/object/bitstring_value.c

@@ -116,17 +116,18 @@ unsigned BitString_Value_Count(void)
 }
 
 /**
- * We simply have 0-n object instances. Yours might be
- * more complex, and then you need to return the index
- * that correlates to the correct instance number
- *
- * @param index Object index
- *
- * @return Index in the object table.
+ * @brief Determines the object instance-number for a given 0..N index
+ * of objects where N is the count.
+ * @param  index - 0..N value
+ * @return  object instance-number for a valid given index, or UINT32_MAX
  */
 uint32_t BitString_Value_Index_To_Instance(unsigned index)
 {
-    return Keylist_Key(Object_List, index);
+    uint32_t instance = UINT32_MAX;
+
+    (void)Keylist_Index_Key(Object_List, index, &instance);
+
+    return instance;
 }
 
 /**