Merge pull request #54 from amalloy/perf

Simplify some code.
last touches on routers
Merge branch 'perf' of github.com:ztellman/lamina into perf
mark beta9
update readme
have periodically not use the scheduled thread pool for actual function invocation
add :period option to subscriptions
add-sub-trace
make zip and merge honor implicit period
mark beta10
add distill-trace and merge-distilled-traces
move around the delayed and periodic invocation functionality, in preparation for a non-wall time task queue
make distill-timing idempotent
fix type-hints for 1.2.x compatibility
cleanup siphon callbacks
no really, make it cancellable
make sure connecting to a closed channel has the proper behavior
Make channel->lazy-seq truly lazy, i.e. not block until first message
arrives in channel.
Merge pull request #55 from baltar/perf

Make channel->lazy-seq truly lazy
callbacks shouldn't be conditional on success