Disable possiblity to delete tags by default

Set default behaviour of translate5 editor to "Not allow user to save segments with tag errors". Still allow deletion of white space tags.

Reason: It often happens, that users accidentally delete tags despite the warning. In some cases this even leads to errors on export.

Therefore it is better to disable this for all translate5 instances by default and also switch all production instances to this behavior. If this is unwanted, than a company needs to switch it on again by running the SQL
UPDATE `Zf_configuration` SET `value` = '1' WHERE `Zf_configuration`.`name` = 'runtimeOptions.segments.userCanIgnoreTagValidation';
 
With TRANSLATE-471 it will be possible to activate this behavior by customer or by task.