Implemented #4561: SHA256 (ECDSAP256SHA256) Algorithm for DNNSEC and Algorithm selector in DNS zone settings.

This removes duplication of the zone_file_prefix var. It might be nice to make it configurable in a follow up.

Update bind_plugin.inc.php to correct "PHP Parse error:  syntax error, unexpected ':' in /usr/local/ispconfig/server/plugins-available/bind_plugin.inc.php on line 279"

improved crojob

This is a considered as stable stable release. (tested the workflow successfully)
Note: I am not perfect at RegEx I know the RegEx for LOC- and DS-Records is actually not checking. The DS-Regex is definitely valid (tested on regexpal).
Along with my dns-status modification this should not be a problem at all.

Next step is to implement some DNSSEC-Requiring Record Types uon request of some others (will be within this branch before removing the WIP state)

Signing is not working, I need a energy drink to proceed...

Supposed behaviour just committing to have a point to roll back ICoE

And found a small bug (privkeys were not deleted on zone deletion) which is now fixed
Testing successful. Doing last test then if everything goes well this will be the new merge request

Signing is not working, I need a energy drink to proceed...

Supposed behaviour just committing to have a point to roll back ICoE

And found a small bug (privkeys were not deleted on zone deletion) which is now fixed
Testing successful. Doing last test then if everything goes well this will be the new merge request