Added Guild# getTextChannelById, getTextChannelsByName, getVoiceChannelById, getVoiceChannelsByName, getRolesByName Reordered the listing of methods in Guild in-line with new mentality of Single object methods first, List methods second. (commit: a1af0d3)
First pass on the Call system. Incomplete, but should maintain the cache for the most part. Fixed cache issues related to removal of relationships. Made EntityBuilder#createMessage update fake user info correct. Create GuildVoiceState and CallVoiceState. Will implement acquring in-process calls on startup later. Needs many events, will implement later. (commit: 012cf6b)