implement an admin command to update the default storage limit without a restart

lib/commands/admin-rpc.js

@@ -110,6 +110,23 @@ var flushCache = function (Env, Server,  cb) {
     cb(void 0, true);
 };
 
+
+// CryptPad_AsyncStore.rpc.send('ADMIN', ['SET_DEFAULT_STORAGE_LIMIT', 1024 * 1024 * 1024 /* 1GB */], console.log)
+var setDefaultStorageLimit = function (Env, Server, cb, data) {
+    var value = Array.isArray(data) && data[1];
+    if (typeof(value) !== 'number' || value <= 0) { return void cb('EINVAL'); }
+    var previous = Env.defaultStorageLimit;
+    var change = {
+        previous: previous,
+        current: value,
+    };
+
+    Env.defaultStorageLimit = value;
+    Env.Log.info('DEFAULT_STORAGE_LIMIT_UPDATE', change);
+
+    cb(void 0, change);
+};
+
 var commands = {
     ACTIVE_SESSIONS: getActiveSessions,
     ACTIVE_PADS: getActiveChannelCount,
@@ -119,6 +136,7 @@ var commands = {
     SHUTDOWN: shutdown,
     GET_FILE_DESCRIPTOR_COUNT: getFileDescriptorCount,
     GET_FILE_DESCRIPTOR_LIMIT: getFileDescriptorLimit,
+    SET_DEFAULT_STORAGE_LIMIT: setDefaultStorageLimit,
 };
 
 Admin.command = function (Env, safeKey, data, _cb, Server) {
@@ -133,7 +151,7 @@ Admin.command = function (Env, safeKey, data, _cb, Server) {
     var command = commands[data[0]];
 
     if (typeof(command) === 'function') {
-        return void command(Env, Server, cb);
+        return void command(Env, Server, cb, data);
     }
 
     return void cb('UNHANDLED_ADMIN_COMMAND');