Add searchall functionality

[markus-fuhrmann]

Here are my changes. Unfortunately there are still small errors in it that I can't find as this is my first time working with php and smarty. I would appreciate support on where the errors are and adding them to the service-desk project.

With the changes you get a list of all created accounts and their status. If the account is not locked, i.e. can be locked, the button should turn red and the lock should be closed. If you click on the button, you can either block or unblock the account.

[coudot]

Thanks for this propositon. We are currently working on core functions to add compatiblity with Active Directory.

After that we'll see what decision we take for this feature.