grid_coords rewrite. Edge cases R hard.

this should squash the bug from rounding glitches.
add error message if grid coords length !== n

just in case.
update minified source
refactor to do bib data bind better

now uses a hierarchical data join.
validate bib sorting choices

fixes failure to update the sorting submenu when the URL is something
like #/bib/ (in which case major === "")
more d3-like bib rendering

instead of just clearing everything and re-adding, this uses the data
join more idiomatically. Requires a little footwork to deal with the
case when the major sort key hasn't changed but the minor has.
fix a sorting glitch

journal-contents order was handling issues wrong. ?: abuse.
update minified source
fix bib.last glitch

Clicking on the "Bibliography" navbar link failed to return to the
previous sorting in some cases (problems when the major sort was the
same as the last major but not the minor).

Also, respond to #/bib/<major> with #/bib/<major>/<default-minor>
update minified source
grid_coords fixing, again

longer rows should go on top whether sgn is positive or negative.

also, allow a user-specified number of columns.

and a user-specified circle radius if the number of columns leads to a
bad circle size with the default calculation.
update minified source
Merge branch 'master' into gh-pages

port in updates