Fixed various CMS_MODULE.install, by not marked module installed if an error occurred!

Improved Auth related module implementation by having a way to change settings like token, max age.
  - use CMS_SETUP.site_id and related "auth.$module.token" ... configuration values.
  - removed related CMS_..._CONSTANTS classes.

For auth session module, use auth_session as table name, and use VARCHAR(64).
Extracted sql from blog module, and store it under site/scripts/install.sql .
Renamed a few $modulename.sql as install.sql

examples/demo/site/modules/session_auth/scripts/install.sql

@@ -0,0 +1,9 @@
+
+CREATE TABLE auth_session (
+   `uid` INTEGER PRIMARY KEY NOT NULL CHECK(`uid`>=0),
+   `access_token` VARCHAR(64)  NOT NULL,
+   `created` DATETIME NOT NULL,
+   CONSTRAINT `uid` UNIQUE(`uid`),
+   CONSTRAINT `access_token` UNIQUE(`access_token`) 
+);
+

examples/demo/site/modules/session_auth/scripts/session_auth_table.sql

@@ -1,11 +0,0 @@
-
-CREATE TABLE session_auth (
-   `uid` INTEGER PRIMARY KEY NOT NULL CHECK(`uid`>=0),
-   `access_token` TEXT  NOT NULL,
-   `created` DATETIME NOT NULL,
-   CONSTRAINT `uid`
-    UNIQUE(`uid`),
-   CONSTRAINT `access_token`
-    UNIQUE(`access_token`) 
-   );
-