AC_HELI_PID: shorten FILT_HZ to FILT, I_L_MIN to ILMI

Also minor formatting fix

libraries/AC_PID/AC_HELI_PID.cpp

@@ -32,17 +32,17 @@ const AP_Param::GroupInfo AC_HELI_PID::var_info[] = {
     // @Description: The maximum/minimum value that the I term can output
     AP_GROUPINFO("IMAX", 5, AC_HELI_PID, _imax, 0),
 
-    // @Param: FILT_HZ
+    // @Param: FILT
     // @DisplayName: PID Input filter frequency in Hz
     // @Description:
-    AP_GROUPINFO("FILT_HZ", 6, AC_HELI_PID, _filt_hz, AC_PID_FILT_HZ_DEFAULT),
+    AP_GROUPINFO("FILT", 6, AC_HELI_PID, _filt_hz, AC_PID_FILT_HZ_DEFAULT),
 
-    // @Param: I_L_MIN
+    // @Param: ILMI
     // @DisplayName: I-term Leak Minimum
     // @Description: Point below which I-term will not leak down
     // @Range: 0 4500
     // @User: Advanced
-    AP_GROUPINFO("I_L_MIN", 7, AC_HELI_PID, _leak_min, AC_PID_LEAK_MIN),
+    AP_GROUPINFO("ILMI", 7, AC_HELI_PID, _leak_min, AC_PID_LEAK_MIN),
 
     // @Param: AFF
     // @DisplayName: Acceleration FF FeedForward Gain

libraries/AC_PID/AC_HELI_PID.h

@@ -25,21 +25,20 @@ public:
 
     /// get_avff - return Acceleration FeedForward Term 
     float       get_aff(float requested_rate);
-    
+
     /// get_leaky_i - replacement for get_i but output is leaded at leak_rate
     float       get_leaky_i(float leak_rate);
-    
+
     // accessors
     float       ff() const { return _vff.get(); }
     void        ff(const float v) { _vff.set(v); }
 
     static const struct AP_Param::GroupInfo        var_info[];
-    
+
 private:
     AP_Float        _vff;
     AP_Float        _leak_min;
     AP_Float        _aff;
 
     float           _last_requested_rate;       // Requested rate from last iteration, used to calculate rate change of requested rate
-    
 };