Remote metrics: use Web API to push/retrieve metrics on remote host. Initial support for multi-value metrics. * Added: Vanity.playground.collecting. You want this to be true only in production environment. When false, disables collecting of metric and experiment data. * Added: Metric.last_update_at. * Removed: Metric.created_at, derived from experiment and never used. Fixed MongoDB flushdb to drop collections. .rvmrc no longer setups Ruby/creates gemset. Apparently on Linux, Passenger uses UNIX sockets, where on OS X it uses TCP.