Units: add imperial with meters.

Fixes of #1609.

src/androidTest/java/de/dennisguse/opentracks/data/models/DistanceFormatterTest.java

@@ -35,7 +35,7 @@ public class DistanceFormatterTest {
     public void testFormatDistance_imperial() {
         DistanceFormatter formatter = DistanceFormatter.Builder()
                 .setDecimalCount(2)
-                .setUnit(UnitSystem.IMPERIAL)
+                .setUnit(UnitSystem.IMPERIAL_FEET)
                 .build(context);
 
         // A large number in imperial

src/androidTest/java/de/dennisguse/opentracks/data/models/SpeedFormatterTest.java

@@ -36,7 +36,7 @@ public class SpeedFormatterTest {
     public void testGetSpeedParts_pace_imperial() {
         SpeedFormatter formatter = SpeedFormatter.Builder()
                 .setDecimalCount(2)
-                .setUnit(UnitSystem.IMPERIAL)
+                .setUnit(UnitSystem.IMPERIAL_FEET)
                 .setReportSpeedOrPace(false)
                 .build(context);
 
@@ -72,7 +72,7 @@ public class SpeedFormatterTest {
     public void testGetSpeedParts_speed_imperial() {
         SpeedFormatter formatter = SpeedFormatter.Builder()
                 .setDecimalCount(2)
-                .setUnit(UnitSystem.IMPERIAL)
+                .setUnit(UnitSystem.IMPERIAL_FEET)
                 .setReportSpeedOrPace(true)
                 .build(context);