Implements a colored background if bind fails to load the zone due to errors
Implements a status text if errors occured
Implements not removing a zone if errors occur. instead old zone stays loaded

Merged language files.

Hide DNSSEC from Wizard if DNS-Mirrors are available (prevents broken DNSSEC-Implementaion on Multiserver-Setups)

Hide DNSSEC from SOA if DNS-Mirrors are available (prevents broken DNSSEC-Implementaion on Multiserver-Setups)

Forgot one template for tooltips as mentioned in: ispconfig/ispconfig3#3995

Fixed issue #3955 DNS module: Limit for maximum zones can be circumvented with "import zone file" function.
Removed TODO string in error template.

This Checkbox can be enabled or disabled by template.

Further I fixed an inconsistent design (HTML) which was introduced by @tbrehm yesterday I tink. (DKIM-Checkbox)

Added sone lines to rmeoting api description file for dns (I hope thats correct...)