Fixed typo in Trim History confirmation.

New: Added warning to Settings -> Misc regarding backlog searching.

NzbDrone.Web/Views/History/Index.cshtml

@@ -2,7 +2,7 @@
 @{ViewBag.Title = "History";}
 @section ActionMenu{
     <ul class="sub-menu">
-        <li>@Ajax.ActionLink("Trim History", "Trim", "History", null, new AjaxOptions{ OnSuccess = "reloadGrid", Confirm = "Delete history items older than 30 days??"})</li>
+        <li>@Ajax.ActionLink("Trim History", "Trim", "History", null, new AjaxOptions{ OnSuccess = "reloadGrid", Confirm = "Delete history items older than 30 days?"})</li>
         <li>@Ajax.ActionLink("Purge History", "Purge", "History", null, new AjaxOptions{ OnSuccess = "reloadGrid", Confirm = "Purge all history items?" })</li>
     </ul>
 }

NzbDrone.Web/Views/Settings/Misc.cshtml

@@ -1,6 +1,11 @@
 @using NzbDrone.Web.Helpers
 @model NzbDrone.Web.Models.MiscSettingsModel
 @{ Layout = null; }
+
+<div class="warningBox">
+    Enabling Backlog searching will use lots of bandwidth, not recommended when using block accounts or you have bandwidth restrictions
+</div>
+
 <div id="stylized">
     @using (Html.BeginForm("SaveMisc", "Settings", FormMethod.Post, new { id = "MiscForm", name = "MiscForm", @class = "settingsForm" }))
     {