Update pynn-brainscales to 2.0-rc5

• a few commits in pynn-brainscales (2), grenade (2), halco (2), hxcomm (2), haldls (1), hwdb (1); contents:
  • add interface-draft for plasticity rules
  • support for requesting server-side information (get_bitfile_info and get_repo_state)
• also cleans up the tag mess in the dependent repositories… → really same tag everywhere
• same for oppulance; as software state didn't change, we don't require oppulance to match pynn-brainscales version (rc2 is sufficient) → relaxing constraint