add new-style schema versions and updater

schema/versions/mysql/6.sql

@@ -0,0 +1,20 @@
+alter table ttrss_entries add column author varchar(250);
+
+update ttrss_entries set author = '';
+
+alter table ttrss_entries change author author varchar(250) not null;
+alter table ttrss_entries alter column author set default '';
+
+create table ttrss_sessions (id varchar(250) not null primary key,
+	data text,
+	expire integer not null,
+	ip_address varchar(15) not null default '',
+	index (id),
+	index (expire)) TYPE=InnoDB;
+
+delete from ttrss_prefs where pref_name = 'ENABLE_SPLASH';
+
+insert into ttrss_prefs (pref_name,type_id,def_value,short_desc,section_id) values('OPEN_LINKS_IN_NEW_WINDOW', 1, 'true', 'Open article links in new browser window',2);
+
+update ttrss_version set schema_version = 6;
+