move requiresOAuthProxy to nginx

we have 3 levels
    * routes, cron, apptask
    * everything else where everyone calls everyone :-)
    * the db layer

src/apps.js

@@ -6,7 +6,6 @@ exports = module.exports = {
     AppsError: AppsError,
 
     hasAccessTo: hasAccessTo,
-    requiresOAuthProxy: requiresOAuthProxy,
 
     get: get,
     getBySubdomain: getBySubdomain,
@@ -281,19 +280,6 @@ function hasAccessTo(app, user, callback) {
     });
 }
 
-function requiresOAuthProxy(app) {
-    assert.strictEqual(typeof app, 'object');
-
-    var tmp = app.accessRestriction;
-
-    // if no accessRestriction set, or the app uses one of the auth modules, we do not need the oauth proxy
-    if (tmp === null) return false;
-    if (app.manifest.addons['ldap'] || app.manifest.addons['oauth'] || app.manifest.addons['simpleauth']) return false;
-
-    // check if any restrictions are set
-    return !!((tmp.users && tmp.users.length) || (tmp.groups && tmp.groups.length));
-}
-
 function get(appId, callback) {
     assert.strictEqual(typeof appId, 'string');
     assert.strictEqual(typeof callback, 'function');