gossip_load: fix get_values_best_feeder

git-svn-id: https://scalaris.googlecode.com/svn/trunk@7129 71766da9-9752-0410-ab17-bfafa751c56a
gossip_load: re-add get_values_all

get_values_all was not reimplemented when moving the value extraction from the
gossip module to the callback module (r7006), but is needed for testing.

git-svn-id: https://scalaris.googlecode.com/svn/trunk@7130 71766da9-9752-0410-ab17-bfafa751c56a
gossip_SUITE: fix gossip_load integration tests

git-svn-id: https://scalaris.googlecode.com/svn/trunk@7131 71766da9-9752-0410-ab17-bfafa751c56a