Applied some cosmetic changess to update_geometry().

- Improved some bad indentation for jQuery command chains,
- Used 'slice' instead of misleading re-use of 'row',
- Fixed document block to resemble geometry block, and
- Removed unused 'index'.
Cached new #table rows into document fragment.

I am now on the verge of insanity, because of the fluency and responsiveness
that exists in Chrome no matter how ineffective my DOM build instructions have
been, and the sluggishness and latency in FireFox on the other hand, that
persist no matter how hard I try!!!
Simplified control flow in update_geometry().

It looks worse but I'll need it some day.
Cashed old #table rows into jQuery collection.

The collection removes itself after the new table rows have been added. This
way the page stays where it was scrolled the last time.
As a bonus, if [name=delayed] is checked, shapes are also removed one by one
from the map. It looks cool!!!
Added <label>s to the login bar.
Fixed eerily adjacent limit text input.

It creeps me out.