Add updateevent documentation, fix bug (#1142)

* Add updateevent documentation

* Fix calendar bug

* updateevent doesn't use id|eventid

src/GamCommands.txt

@@ -1005,7 +1005,6 @@ The following attributes are equivalent:
 	guestscantinviteothers|
 	guestscantseeothers|
 	hangoutsmeet|
-	(id <String>)|
 	(location <String>)|
 	(noreminders| (reminder <Number> email|popup|sms))|
 	(optionalattendee <EmailAddress>)|
@@ -1019,6 +1018,11 @@ The following attributes are equivalent:
 	(timezone <Timezone>)|
 	(visibility default|public|prvate)
 
+<EventUpdateAttributes> ::=
+	<EventAttributes>|
+	(removeattendee <EmailAddress>)|
+	(replacedescription <RegularExpression> <String>)
+
 <EventSelectProperty:> ::=
 	(after <Time>)|
 	(before <Time>)|
@@ -1030,9 +1034,10 @@ The following attributes are equivalent:
 <EventDisplayProperty> ::=
 	(timezone <TimeZone>)
 
-gam calendar <CalendarItem> addevent <EventAttributes>+ [<EventNotificationAttribute>]
+gam calendar <CalendarItem> addevent [id <String>] <EventAttributes>+ [<EventNotificationAttribute>]
 gam calendar <CalendarItem> deleteevent id|eventid <EventID> [doit] [<EventNotificationAttribute>]
 gam calendar <CalendarItem> moveevent id|eventid <EventID> [doit] [<EventNotificationAttribute>]
+gam calendar <CalendarItem> updateevent <EventID> <EventUpdateAttributes>+ [<EventNotificationAttribute>]
 gam calendar <CalendarItem> wipe
 gam calendar <CalendarItem> printevents <EventSelectProperty>* <EventDisplayProperty>* [todrive]
 

src/gapi/calendar.py

@@ -370,6 +370,7 @@ def getEventAttributes(i, calendarId, cal, body, action):
         elif myarg == 'replacedescription' and action == 'update':
             search = sys.argv[i+1]
             replace = sys.argv[i+2]
+            if 'description' in body:
                 body['description'] = re.sub(search, replace, body['description'])
             i += 3
         elif myarg == 'start':