Calculator conversion fix

Switching between F and C now automatically changes bullet point 3 from
GPM options to LPM options. The calculator has also been updated to
correctly calculate the number of units given these new changes.
Alternate text has been added so that the message shown after
calculating shows the LPM if that was the unit of measurement selected.
There was also a bug where the number of units suggested was showing up
as the number of showers selected in the post calculation message. This
bug has been fixed.
Merge branch 'tb-calculatorconvertfix'