Explain step="any" in harvest _form view.

app/views/harvests/_form.html.haml

@@ -22,6 +22,9 @@
   .control-group
     = f.label 'How many?', :class => 'control-label'
     .controls
+      -# Some browsers (eg Firefox for Android) assume "number" means
+      -# "integer" unless you specify step="any":
+      -# http://blog.isotoma.com/2012/03/html5-input-typenumber-and-decimalsfloats-in-chrome/
       = f.number_field :quantity, :class => 'input-small', :step => 'any'
       = f.select(:unit, Harvest::UNITS_VALUES, {:include_blank => false}, :class => 'input-medium')