Actually fix masterPlugins visibility

The masterPlugins array should not be a global.  The ejs templates
already have it provided through locals.masterPlugins and plugins get it
through onLoadFinish.  Make masterPlugins local to master.js again and
fix the ejs templates to use locals.masterPlugins.

master.js

@@ -1012,7 +1012,7 @@ async function getPlugins(){
 }
 
 
-masterPlugins = await getPlugins();
+var masterPlugins = await getPlugins();
 
 
 io.attach(server);

static/nav.html

@@ -14,8 +14,8 @@
     <%# Very ugly ejs code to hide the Players button if the playerManager plugin isn`t installed %>
     <%
     sidebarPluginButtonsHtml = "";
-    for(let o in masterPlugins){
-    let plug = masterPlugins[o];
+    for(let o in locals.masterPlugins){
+    let plug = locals.masterPlugins[o];
     if(plug.main
     && plug.main.ui
     && typeof plug.main.ui.sidebar == "object"

static/nodes.html

@@ -40,8 +40,8 @@
                                 </ul>
 							${findInArray("modName", "remoteMap", slave.mods).length ? "<a href='/remoteMap?instanceID="+id+"'>Remote map</a>" : ""}
 						`
-						for(let o in masterPlugins){
-							let plug = masterPlugins[o];
+						for(let o in locals.masterPlugins){
+							let plug = locals.masterPlugins[o];
 							if(plug.main
 							&& plug.main.ui
 							&& typeof plug.main.ui.slaveListing == "object"