Security enhancement in .htaccess

Prevent .ht* files from being sended to outside requests
(cherry picked from commit 53bda3d)
Added test to check if htaccess file is accessible (cherry picked from commit d24ce21)
bug fix #5842 Module settings default values are not shown before module activation.

Do not check whether default value for arr and aarr is an array, as it is checked in _arrayToMultiline and from metadata you can only pass arrays.
Adding handling of other settings default values, not only arr and aarr.
Adding handling for bool values to accept string, bool and int values ('true', true, 1, 'on'...).
Changing language messages in translation files for invalid modules.