Rephrase some English locale bits.

Hopefully makes them more intuitively understandable now.

locale/en/locale.cfg

@@ -3,7 +3,7 @@ sensor.day_time.format=It's __1__. Brightness: __2__.
 sensor.day_time.day_format=It's __1__ on day __2__. Brightness: __3__
 sensor.day_time.settings.title=Time of day settings
 sensor.day_time.settings.show_day_number=Show the current planetary day since landing.
-sensor.day_time.settings.minute_rounding=Round minutes to the nearest 15.
+sensor.day_time.settings.minute_rounding=Round displayed minutes to a quarter hour (xx:15, xx:30, etc).
 
 sensor.evolution_factor.name=Evolution factor
 sensor.evolution_factor.format=Biter evolution: __1__.
@@ -29,7 +29,7 @@ settings_title=EvoGUI settings
 
 settings.core_settings.title=Core settings (shared)
 settings.core_settings.update_freq_left=Update EvoGUI every
-settings.core_settings.update_freq_right=ticks (60 ticks = 1 second)
+settings.core_settings.update_freq_right=ticks (there are 60 ticks in a second)
 
 settings.sensors_frame.title=Sensor settings