Fix doc and mysql min version

ChangeLog

@@ -150,6 +150,8 @@ WARNING:
 
 Dolibarr 3.9 is not yet fully compatible with PHP 7.
 
+Mysql minimum version is now 5.0.3 
+
 Following changes may create regression for some external modules, but were necessary to make
 Dolibarr better:
 - Deprecated Product::setPriceExpression. Use Product::update instead

htdocs/core/db/mysql.class.php

@@ -38,7 +38,7 @@ class DoliDBMysql extends DoliDB
 	//! Database label
 	const LABEL='MySQL';
 	//! Version min database
-	const VERSIONMIN='4.1.0';
+	const VERSIONMIN='5.0.3';
 	/** @var resource Resultset of last query */
 	private $_results;
 

htdocs/core/db/mysqli.class.php

@@ -38,7 +38,7 @@ class DoliDBMysqli extends DoliDB
     //! Database label
     const LABEL='MySQL or MariaDB';
     //! Version min database
-    const VERSIONMIN='4.1.3';
+    const VERSIONMIN='5.0.3';
 	/** @var mysqli_result Resultset of last query */
 	private $_results;