fix(junk): extend list of junk icon available

Documentation/SOGoInstallationGuide.asciidoc

@@ -2897,9 +2897,18 @@ SOGoMailJunkSettings = {
 ----
 
 |D |mailJunkIcon
-|Choose the Junk icon. For the thumb down `thumb_down`, for a shield `gpp_bad`.
+|Choose the Junk icon. Values are :
+https://materialui.co/icon/thumb-down[thumb_down],
+https://materialui.co/icon/gpp-bad[gpp_bad],
+https://materialui.co/icon/local-fire-department[local_fire_department],
+https://materialui.co/icon/bug-report[bug_report],
+https://materialui.co/icon/error[error],
+https://materialui.co/icon/warning[warning],
+https://materialui.co/icon/dangerous[dangerous] and
+https://materialui.co/icon/report-gmailerrorred[report_gmailerrorred].
 
-Defaults to `gppthumb_down_bad`.
+
+Defaults to `thumb_down`.
 
 |D |SOGoMailKeepDraftsAfterSend
 |Parameter used to keep mails in the drafts folder once they have been

SoObjects/SOGo/SOGoDomainDefaults.m

@@ -486,7 +486,15 @@
   NSArray *iconsList;
   NSString *icon;
 
-  iconsList = [NSArray arrayWithObjects: @"thumb_down", @"gpp_bad", nil];
+  iconsList = [NSArray arrayWithObjects: @"thumb_down",
+                                          @"gpp_bad",
+                                          @"local_fire_department",
+                                          @"bug_report",
+                                          @"error",
+                                          @"warning",
+                                          @"dangerous",
+                                          @"report_gmailerrorred",
+                                          nil];
   icon = [self objectForKey: @"mailJunkIcon"];
   if (([icon length] && ![iconsList containsObject:icon]) || ![icon length])
   {