Update comment.
Support syntax sugar for initializing lattices.

Closes #294. Rather than writing

    foo <= Bud::MaxLattice.new(5)

you can now write

    foo <= 5

Unfortunately, due to a bug in the superator gem, this syntax sugar does not
work with the <+ operator.
Fix wrong output for notin self joins.

Closes #298. The implementation is somewhat ugly (we need to special-case self
joins in the notin code), but I didn't see a cleaner fix.

Note that evaluation of notin self joins is still a bit silly, because we send
the notin operator two copies of each input. That seems easy enough to fix, but
I'll leave that for later.
Merge pull request #295 from JoshRosen/marshal-fallback

Automatically fall back to Marshal when marshaling tuples
Code review for marshaling of nested lattices.

See #295. Improve test case, move some state to be instance variables rather
than local variables, and update the release notes.
Update release date for 0.9.6
Make lset#inspect produce prettier results.

Remove the redundant "Set:" output from lset#inspect. Along the way, fix a test
failure with MRI 1.8 -- apparently Set#inspect in MRI 1.8 does not produce
sorted output.
Replace usage of Object#id with Object#object_id.

Object#id is deprecated in MRI 1.8 and has been removed in MRI 1.9.
Fix notin test failure with MRI 1.8.

We can't use columns named "id" in MRI 1.8.
Set executable permission bits on budlabel tool.
Update WIP version number to 0.9.7
Add "backports" gem as a dependency.

This is not required for bud itself, but some of the examples (e.g., chat) make
use of it; it is a relatively harmless dependency, so just add it to simply the
first-time UX.
Add .travis.yml file for Travis CI.