Version 1.2.12 : include joomla 1.5.15 installation directory

This multisite joomla version is bundled with latest joomla 1.5.15 installation directory and the jms patches definition 1.2.15 to 1.2.18.

It also fix minor JMS tools warning that may happen when the joomla environment is inconsistent or that some modules have been deleted manually without using the joomla uninstall.
It also fix a minor icon type "without tables" in the JMS tools that may happen on some extension. This does not impact the processing - just the display that was not accurate in some cases.

The patch definition 1.2.18 add JMS tools definition for "hot property" modules and plugins.