Provide a default date for lists and cards creation date

See https://github.com/wekan/wekan/pull/362#issuecomment-149645497
for motivation.

This commit also contains cosmetic changes to the import Popup and
on the code style to be more consistent with the code base.

client/components/main/popup.styl

@@ -17,9 +17,11 @@ $popupWidth = 300px
     margin: 4px -10px
     width: $popupWidth
 
+  p,
+  textarea,
   input[type="text"],
   input[type="email"],
-  input[type="password"]
+  input[type="password"],
   input[type="file"]
     margin: 4px 0 12px
     width: 100%
@@ -30,8 +32,6 @@ $popupWidth = 300px
 
   textarea
     height: 72px
-    margin: 4px 0 12px
-    width: 100%
 
   .header
     height: 36px