v0.8.0 – player heads

• Player heads as icons: head:<name or uuid> wherever an item id goes (YAML icon:, API
  Icon.head(...), grids, lists, buttons). The client draws heads as 8 x 8 px and only on its 9 px
  text grid; so that a head still sits in the middle of its button, row or cell, the element moves
  with it (up to 4 px) and the log names the y that avoids the move (table in docs/menus.md).
  Lists with heads want a row height of 9 or 18, grids a cell pitch of 18 or 27; lists of
  online-players default to 18 px rows. Online players send their skin along. Heads also appear in
  the plain dialog, in front of the label.
• Placeholders work in the icon of icon elements and buttons (icon: "head:%player%").
• Buttons whose height is no multiple of the tile size center their text and icon on the height
  that is actually drawn (a 20 px button is drawn 16 px high); before, the text sat too low.
• Lists that mix heads and item icons put both in one 16 px column, so all texts start at the same x.
• Dynamic lists of online-players have %item_head% (and %item_icon%) for the player's head;
  beispiel-spieler.yml uses it.

Downloads: Glyphwork-0.8.0.jar (plugin), glyphwork-api-0.8.0.jar (compile against it, do not shade), glyphwork-example-0.8.0.jar (example plugin, optional).