Dummy data: relink counting video to top
Merge remote-tracking branch 'github/gui'
Add package object to dbrary with cast and unwords
Upgrade to play 2.1.4
Enhance Columns -> Selector that has from clause

This simplifies many queries and somewhat un-confuses the parallel
row/column/src values.
Fetch and store volume creation time

Since it is used pervasively.  Should review for similar optimizations.
Remove stray close-parens in citation
Re-add id to object_segment.

Not sure why I removed it.
Improve slot range display; add slot add button
Add record selection to slot edit page

Not the prettiest, and doesn't check for duplicate records, but works.
Fixes assembla-51
Fix assembla-114: attempt to authorize everybody

Don't provide system accounts (everybody, databrary) as options for
authorization.  The only possible exception might be if people do in
fact request authorization directly under Databrary, but this could
likely be handled through another interface.
Various optimizations around access and authorization

Add some caching, change some semantics to match uses, update older
code.
Create full slots using trigger on container

This doesn't actually simplify code but does simplify assumptions.
Unfortunately this doesn't really ensure that the full slot always
exists, but we'll assume it does for now.
js messages and message handler in place. errors not yet tested.