Merge pull request #59 from amalloy/perf

Remove duplication in number-handling code
add query-seqs and query-streams
mark beta13
back to snaphshot
allow for multiple listeners on results
make executor resizing a little more responsive
get rid of :lamina/enqueued
don't force subscription on results with listeners
expose results from all paths, and only do queue backprop when using bridge-in-order
add pmap*, turn off argument capture by default, and fix query-seqs where no seq is specified
Fix handling of nil in query-seqs