commented speed saved in units of MPH

constants.h

@@ -218,7 +218,7 @@ class Location {
   char recordType[4];      // GPS, power-up, first valid time, etc
   PointGPS loc;            // has-a lat/long, degrees
   time_t timestamp;        // has-a GMT time
-  uint8_t numSatellites;   // number of satellites in view
+  uint8_t numSatellites;   // number of satellites in use (not the same as in view)
   float speed;             // current speed over ground in MPH
   float direction;         // direction of travel, degrees from true north
   float altitude;          // altitude, meters above MSL

model_breadcrumbs.h

@@ -19,7 +19,7 @@
             If the controller tells us to save to file, don't tell the "model" to do anything.
 
             When should the controller should remember a new breadcrumb?
-            1. Every five minutes
+            1. Every ten minutes
             2. When we drive a visible distance on the screen
             3. When we drive into a new 6-digit grid square (todo)
             4. When we turn a sharp corner (todo)
@@ -190,9 +190,9 @@ class Breadcrumbs {
     }
   }
 
-  void rememberGPS(PointGPS vLoc, time_t vTime, uint8_t vSats, float vSpeed, float vDirection, float vAltitudeMeters) {
+  void rememberGPS(PointGPS vLoc, time_t vTime, uint8_t vSats, float vSpeedMPH, float vDirection, float vAltitudeMeters) {
     time_t cutoff = makeTime(GRIDUINO_FIRST_RELEASE);
-    Location gps{rGPS, vLoc, vTime, vSats, vSpeed, vDirection, vAltitudeMeters};
+    Location gps{rGPS, vLoc, vTime, vSats, vSpeedMPH, vDirection, vAltitudeMeters};
     if (vTime > cutoff) {
       remember(gps);
     } else {