[geary] Add translator notes about the conversation email star/unstar buttons.

[Michael Gratton <mjog src gnome org>]

commit bc4c1e15790a83421e488acceeaa8a0b100e737f
Author: Michael James Gratton <mike vee net>
Date:   Wed Dec 14 11:49:24 2016 +1100

    Add translator notes about the conversation email star/unstar buttons.

 ui/conversation-email.ui |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/ui/conversation-email.ui b/ui/conversation-email.ui
index 3bfb2a8..9e5e494 100644
--- a/ui/conversation-email.ui
+++ b/ui/conversation-email.ui
@@ -47,7 +47,7 @@
         <property name="sensitive">False</property>
         <property name="can_focus">True</property>
         <property name="receives_default">True</property>
-        <property name="tooltip_text" translatable="yes">Mark this message as starred</property>
+        <property name="tooltip_text" translatable="yes" comments="Note: The application will never show 
this button at the same time as unstar_button, one will always be hidden.">Mark this message as 
starred</property>
         <property name="valign">start</property>
         <property name="action_name">eml.star</property>
         <property name="relief">none</property>
@@ -69,7 +69,7 @@
         <property name="sensitive">False</property>
         <property name="can_focus">True</property>
         <property name="receives_default">True</property>
-        <property name="tooltip_text" translatable="yes">Mark this message as not starred</property>
+        <property name="tooltip_text" translatable="yes" comments="Note: The application will never show 
this button at the same time as star_button, one will always be hidden.">Mark this message as not 
starred</property>
         <property name="valign">start</property>
         <property name="action_name">eml.unstar</property>
         <property name="relief">none</property>