Integrate schema change necessary for microsub

sql/MySQL/6.sql

@@ -4,6 +4,8 @@
 
 -- Please consult the SQLite 3 schemata for commented version
 
+alter table arsse_tokens add column data longtext default null;
+
 alter table arsse_users add column num bigint unsigned unique;
 alter table arsse_users add column admin boolean not null default 0;
 alter table arsse_users add column lang longtext;

sql/PostgreSQL/6.sql

@@ -4,6 +4,8 @@
 
 -- Please consult the SQLite 3 schemata for commented version
 
+alter table arsse_tokens add column data text default null;
+
 alter table arsse_users add column num bigint unique;
 alter table arsse_users add column admin smallint not null default 0;
 alter table arsse_users add column lang text;

sql/SQLite3/6.sql

@@ -2,6 +2,10 @@
 -- Copyright 2017 J. King, Dustin Wilson et al.
 -- See LICENSE and AUTHORS files for details
 
+-- Add a column to the token table to hold arbitrary class-specific data
+-- This is a speculative addition to support OAuth login in the future
+alter table arsse_tokens add column data text default null;
+
 -- Add multiple columns to the users table
 -- In particular this adds a numeric identifier for each user, which Miniflux requires
 create table arsse_users_new(