Invert check out form expiration fields

Improve clarity by selecting first the unit then the quantity.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

mayan/apps/checkouts/widgets.py

@@ -16,16 +16,15 @@ class SplitTimeDeltaWidget(forms.widgets.MultiWidget):
     """
     def __init__(self, attrs=None):
         widgets = (
+            forms.widgets.Select(
+                attrs={'style': 'width: 8em;'}, choices=TIME_DELTA_UNIT_CHOICES
+            ),
             forms.widgets.NumberInput(
                 attrs={
                     'maxlength': 4, 'style': 'width: 8em;',
                     'placeholder': _('Period')
                 }
-            ),
-            forms.widgets.Select(
-                attrs={'style': 'width: 8em;'}, choices=TIME_DELTA_UNIT_CHOICES
-            ),
-
+            )
         )
         super(SplitTimeDeltaWidget, self).__init__(widgets, attrs)