Print 'today' instead of 'just now'

The arrow library returns more fine grained humanized dates, taking time
of the day into account. topydo only works with dates, so 'just now'
actually means 'today'.

See also this arrow issue which requests more coarse grained human
dates:

https://github.com/crsmithdev/arrow/issues/96

test/test_list_format.py

@@ -132,7 +132,7 @@ class ListFormatTest(CommandTest):
         command.execute()
 
         result = """|  1| D Bar @Context1 +Project2                (3 months ago, due a month ago, started a month ago)
-|  2| Z Lorem ipsum dolorem sit amet. Red @f... lazy:bar (just now, due in 2 days, starts in a day)
+|  2| Z Lorem ipsum dolorem sit amet. Red @fox ... lazy:bar (today, due in 2 days, starts in a day)
 |  3| C Foo @Context2 Not@Context +Project1 Not+Project                              (4 months ago)
 |  4| C Baz @Context1 +Project1 key:value
 |  5| Drink beer @ home
@@ -183,7 +183,7 @@ x 2014-12-12
         command.execute()
 
         result = """3 months ago | a month ago | a month ago |
-just now | in 2 days | in a day |
+today | in 2 days | in a day |
 4 months ago | | |
 | | |
 | | |
@@ -278,7 +278,7 @@ just now | in 2 days | in a day |
         command.execute()
 
         result = """3 months ago
-just now
+today
 4 months ago
 
 
@@ -330,7 +330,7 @@ due in 2 days, starts in a day
         command.execute()
 
         result = """3 months ago, due a month ago, started a month ago
-just now, due in 2 days, starts in a day
+today, due in 2 days, starts in a day
 4 months ago
 
 

topydo/lib/ListFormat.py

@@ -42,7 +42,7 @@ def humanize_date(p_datetime):
     """ Returns a relative date string from a datetime object. """
     now = arrow.now()
     date = now.replace(day=p_datetime.day, month=p_datetime.month, year=p_datetime.year)
-    return date.humanize()
+    return date.humanize().replace('just now', 'today')
 
 def humanize_dates(p_due=None, p_start=None, p_creation=None):
     """