added join function which doesnt have a trailing delimiter

multiply now calls the util_tal_join function. also added tests
for util_tal_join
db_query_fmt now uses explicit binding param indices

using explicit indices means we only have to bind once for
each query variable. also added some more tests and fixed some
minor bugs.
printing search results to aug-db window now

trying to figure out refresh bug with results
derived window. for some reason werase doesnt
cut it and some old stuff gets left in the window
when we refresh with new results. seems like
curses isnt properly recognizing which parts of
the window need to be redrawn.