Add expt_swap_uid to experiments table so we can track last person

to swap in/out/modify an experiment, so we can do proper accounting.

sql/database-create.sql

@@ -253,6 +253,7 @@ CREATE TABLE experiments (
   expt_terminating datetime default NULL,
   expt_locked datetime default NULL,
   expt_swapped datetime default NULL,
+  expt_swap_uid varchar(8) NOT NULL default '',
   swappable tinyint(4) NOT NULL default '0',
   priority tinyint(4) NOT NULL default '0',
   batchmode tinyint(4) NOT NULL default '0',

sql/database-migrate.txt

@@ -561,3 +561,10 @@ last_net_act,last_cpu_act,last_ext_act);
 
         alter table veth_interfaces change vnode vnode_id varchar(32)
 		default NULL;
+
+1.147: Add expt_swap_uid to experiments table to store who was the
+       last to swap in/out/modify an experiment. Needed for proper
+       user accounting.
+
+        alter table experiments add expt_swap_uid varchar(8) NOT NULL
+		 default '' after expt_swapped;