v0.5

Changes:

• Add group chat support and helper commands for group chats:
  • /names: get list of users in current group chat
  • /invite <user>: invite user to current group chat
  • /join: join the current group chat (after getting invited)
  • /part: leave current group chat
• Add history searching: search the history with / and then jump to next
  match with n and previous match with p
• Add F10 hotkey to jump from a conversation to first URL starting with
  http in its history and also switch to zoomed view
• Add support for the nuqql-matrixd backend
• Cleanups, fixes, and improvements
• Requires purpled v.4, nuqql-slixmppd v0.3, or nuqql-matrixd v0.1