Added support for path_aliases.

Refactored CMS_MODULE.router (..): WSF_ROUTER design,
  to create only one router object of type CMS_ROUTER.
Added optional CMS_NODE.link: CMS_LOCAL_LINK
Reviewed permissions related to node module.
Refactor and add CMS_STORAGE_SQL(_BUILDER) abstractions
   for implementation relying only on SQL statements.
Factorized sql builder initialization (to work for sqlite and mysql storage builders).
Added CMS_RESPONSE.formatted_string (a_text: READABLE_STRING_GENERAL; args: TUPLE): STRING_32
Added function "translation", but not implemented for now.
Updated indexing notes and comments.
Code cleaning.

examples/demo/site/scripts/user.sql

@@ -0,0 +1,34 @@
+BEGIN;
+
+CREATE TABLE "users"(
+  "uid" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL CHECK("uid">=0),
+  "name" VARCHAR(100) NOT NULL,
+  "password" VARCHAR(100) NOT NULL,
+  "salt" VARCHAR(100) NOT NULL,
+  "email" VARCHAR(250) NOT NULL,
+  "status" INTEGER,
+  "created" DATETIME NOT NULL,
+  "signed" DATETIME,
+  CONSTRAINT "name"
+    UNIQUE("name")
+);
+
+CREATE TABLE "roles"(
+  "rid" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL CHECK("rid">=0),
+  "name" VARCHAR(100) NOT NULL,
+  CONSTRAINT "name"
+    UNIQUE("name")
+);
+
+CREATE TABLE "users_roles"(
+  "uid" INTEGER NOT NULL CHECK("uid">=0),
+  "rid" INTEGER NOT NULL CHECK("rid">=0)
+);
+
+CREATE TABLE "role_permissions"(
+  "rid" INTEGER NOT NULL CHECK("rid">=0),
+  "permission" VARCHAR(255) NOT NULL,
+  "module" VARCHAR(255)
+);
+
+COMMIT;