range aid: added hysteresis for switching in and out of range aid

- prevents rapid switching
- added innovation consistency check for using range aid

Signed-off-by: Roman <bapstroman@gmail.com>

EKF/ekf.cpp

@@ -57,6 +57,7 @@
 #define ISFINITE(x) __builtin_isfinite(x)
 #endif
 
+
 bool Ekf::init(uint64_t timestamp)
 {
 	bool ret = initialise_interface(timestamp);