Converted MySQL migration history to the new format

Replaced all NNN_StoreName.sql migration resources with a more
readable, single-file-per-store

OpenSim/Data/MySQL/Resources/LogStore.migrations

@@ -0,0 +1,13 @@
+
+:VERSION 1
+
+CREATE TABLE `logs` (
+  `logID` int(10) unsigned NOT NULL auto_increment,
+  `target` varchar(36) default NULL,
+  `server` varchar(64) default NULL,
+  `method` varchar(64) default NULL,
+  `arguments` varchar(255) default NULL,
+  `priority` int(11) default NULL,
+  `message` text,
+  PRIMARY KEY  (`logID`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;