@scrutinizer-notifier noticed that the $pageid might be false when
page_findnearest looks for it.

This is needed to accomodate for the change in page_findnearest()

This means that templates that use this function will no longer display
pages like sidebars that can't be accessed by the current user.

This allows to quickly check if a variable is empty but keeps strings
and numbers evaluating to zero.

Sorting by the sort number is too confusing since those are assigned
independently by different authors

You now can add labels that don't wrap around inputs, but you have to
ensure IDs are properly assigned yourself.

The Label class has been renamed to LabelElement to reflect the naming
scheme of the other elements.

This event handles both known core types and unknown types as default

edit translation of the user 青子守歌

re-add PR #470 again.