I found that the strict heirarchy was not satisfying the situation
where one tag is the intersection of two others, but we can only
pick one as the parent
For example, does red_jacket belong under clothes.red_clothes or
clothes.jackets? A search for "red_clothes AND jackets" might
give us someone wearing red pants and a black jacket, so this
definitely needs to be a separate tag, but picking only one
parent for it is not sufficient. Now, a search for red_clothes
and a search for jackets will both find our red_jacket photo.
The change also applies to Albums because why not, and I'm sure
a similar case can be made.
Unfortunately this means tags no longer have one true qualname.
The concept of qualnames has not been completely phased out but
it's in progress.
This commit is very big because I was not sure for a long time
whether to go through with it, and so much stuff had to change
that I don't want to go back and figure out what could be grouped
together.
By default, photos with searchhidden do not appear in the search
results. This allows a small number of representative images from
a large album to appear in the results, while the rest can be
found on the album's page.
The same effect could be achieved with a tag and forbid search,
but tag searching has much higher cost and it would be more difficult
to implement as a default behavior without requiring lots of special
checks whenever listing tags etc.
Any element with class clipboard_size will have its text updated;
Removed the call to on_pageload from save_ because it redundantly
causes a load. Separate those update hooks.
