Update of Event/Mailer/JEM/Script.php + update sql

Event.php
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+ fixed postSaveHook(): $isNew and $id was wrong for new events -> no eMail sent; get data from model instead


Jem.php
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+ renamed 'el*' to 'jem*' (to allow EL and JEM working independent at same site)


Mailer
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+ changed "$this->params->get('receivers')" to "$this->_receivers" to allow admin mails to system mail receivers only (empty "receivers" field)
+ completely reworked onEventEdited() and onVenueEdited() to allow new events/venues
  (2nd param "edited" is "isNew" by sender (inverse), "$edited" was used multiple times with different meaning - now named $isNew or $modified)
+ _mailer() prepared to use "BCC" instead of "To" - requires new $data->useBCC flag to implement (incl. backend setting)


Script.php
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+ new function deleteObsoleteFiles() to delete all obsolete files and folders, called in preflight()
+ new function updateJemMenuItems195() to increment all catids in menu item params as needed, called in postflight()
+ new function updateJemModules195() to increment all catids in module params as needed, called in postflight()


Update.sql
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+ on #__menu change link '...&view=myattending' to '...&view=myattendances'
+ on #__menu increment catid on link '...&view=category&id=%'