Performance improvement on calendar and gantt (about 45% on gantt for large number of issues).

Partial issues/_tooltip is replaced by an helper and some translated strings are now cached.

git-svn-id: http://redmine.rubyforge.org/svn/trunk@794 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/views/projects/calendar.rhtml

@@ -49,7 +49,7 @@ while day <= @date_to
         <%= h(truncate(i.subject, 30)) %>
 		</small>
         <span class="tip">
-        <%= render :partial => "issues/tooltip", :locals => { :issue => i }%>
+        <%= render_issue_tooltip i %>
         </span>		
 		</div>
 		<% else %>

app/views/projects/gantt.rhtml

@@ -192,7 +192,7 @@ top = headers_height + 10
 	<% # === tooltip === %>
 	<div class="tooltip" style="position: absolute;top:<%= top %>px;left:<%= i_left %>px;width:<%= i_width %>px;height:12px;">
 	<span class="tip">
-    <%= render :partial => "issues/tooltip", :locals => { :issue => i }%>
+    <%= render_issue_tooltip i %>
 	</span></div>
 <% else 
     i_left = ((i.start_date - @date_from)*zoom).floor