Log Message:
Changes 1.8.4:
* AI:
  * Fixed bug #16102: Made AI cancel attacks if a previously valid attack
    was made invalid by WML event after move in move+attack sequence.
  * Allowed custom eras to define Lua AI modifications for games played with
    this era.
* Campaigns:
  * Delfadors Memoirs:
    * Make Lionel's portrait in Delfador's Memoirs story
      screens the same as his unit portrait since there doesn't seem to be a
      current higher-res version available
  * Descent into Darkness:
    * Made 'Alone at Last' slightly easier. Also, Dela is no longer
      invulnerable but cannot be assassinated easily.
  * Legend of Wesmere:
    * removed gold overlay when defeating both leaders
    * Reduced the difficulty of scenario 14 and improved the AI of the ally.
  * Liberty:
    * Increased the difficulty in 'Glory' by making the defenders behave more
      intelligently.
* Language and i18n:
  * Updated translations: Chinese (Simplified), Galician, Japanese, Serbian,
    Vietnamese
  * Flushed image cache when changing language
* Miscellaneous and bug fixes:
  * Ensured graceful failure when encountering broken [advancefrom] tag.
  * Handled ToD areas in a LIFO way, so that it is possible
    to override them without first removing them
  * Avoided displaying an empty menu and therefore choosing
    a random weapon, when there is none
  * Added detection for server replays, as they are missing the core [lua] tags
  * Fixed attack_end event not raised for uncommon swarm attacks
  * Added test for invalidated death due to positive hp after the 'die' event
  * 1.9 syntax creeped into 1.8.x causing segfaults
  * Fixed petrifying in multiround combats
  * Fixed reference binded to a temporary, possibly the cause of the failure
    on arklinux
  * Never allow uploading *.pbl files (case-insensitive) to the add-ons
    server from the regular game client
  * Fixed revision.hpp generation with cmake 1.8(.2)
  * Fixed usage of first PKG_CHECK_MODULES inside a shell conditional
  * Fixed broken attack animatio