Fix strings, style, tabulation code,

Fix strings, style, tabulation code,
Improvement of attachments tab

For attachments into event and venue.
review mailer plugin

new version with review/change of Bluefox (thanks) and others small
modification.
Can delete event image & venue image

Include delete event image and venue image from FE.
added reference to backend helper to jem.php, FIX #701
added googleApi-option for output googlemap, REF #696

- Google API option has been added so there are now 3 options
- the classes for output of the mapicon/flyerimage has been altered
- hidden input fields have been added
- infobox.js +googlemap.js _ googlemap.css are added
altered default value of global tld/lg when no option selected

when no option is selected the value of the fields are blanked
altered function getVenue (model-venue,front), FIX #706
altered reference to function mapicon (tmp-venues, front), REF #696
Fix Warning: Illegal string offset 'class' ...

This PR fix:
Warning: Illegal string offset 'class' in ../libraries/cms/html/html.php on line 965
Warning: Illegal string offset 'class' in .../libraries/cms/html/html.php on line 966

+ a bit code style and prevert issues like we have for the calender field.
Merge pull request #708 from zero-24/patch-1

Fix Warning: Illegal string offset 'class' ...
changed display tooltip/link of attachments (front)

* image+name are now in 1 field
* tweaked css a bit
* removed references of el-
* tooltip of attachment includes name/file/description
added venue-attachments to event-view (front)

not sure why it was not there but when a venue has attachments and the
venue is shown at the venue page it does show the attachments of the
venue now to.
added array-attribs to select.genericlist
added ownedvenuesonly to globalattribs, REF #443
added ownedvenuesonly to globalattribs, related to #443
removed obsolete event-file class from css
added title-attrib to attachment pages
added some missing language strings
deleted obsolete zip-file