also fixed some inconsistency between client and server validation.

Total 0 items. when list is empty.
and showing x out of x for n>0 and paging on.

When we do not want an attribute to be searched we do not define it in
the filter model, or mark it inctive in the scenario when we use the
original model.
GridView should not try to access the attribute then and automatically
not display the filter field.

consistent api for safe and required

fixes #929

when error occurs while handling errors output was not readable in web
context

fixes #964

not need to suggest packages in core. They are required by extension
composer.json anyway.

fixes #963

fixes #961

adjust depended asset position or throw exception on conflict

Fixes issue #934. Command is created for the selected database, not the default database.

goBack() will redirect user to his returnUrl
fixes #925

added version information