dmap: Rename hash_table to hash_tables
dmap: Rename hash_table to hash_tables

https://bugzilla.gnome.org/show_bug.cgi?id=746722

GNOME/grilo-plugins,jasuarez/grilo-plugins,MikePetullo/grilo-plugins,jasuarez/grilo-plugins,grilofw/grilo-plugins,GNOME/grilo-plugins,MikePetullo/grilo-plugins,grilofw/grilo-plugins,MikePetullo/grilo-plugins