New Feature: Optional highlights shown in server window

Added an option that allows users to have their highlights shown in the server window, so they won't be lost in small buffers or busy chats. Also added myself to contributors.

Modified Yaaic files:
/res/values/strings.xml - added "settings_highlight_notice_*" values in Highlight
/res/values/settings.xml - added "*_highlight_notice" values for Highlight options
/res/xml/preferences.xml - added CheckBoxPreference to Highlight options
/src/org/yaaic/irc/IRCConnection.java - added service.getSettings().isHighlightMsgEnabled() and called it in relevant methods
/src/org/yaaic/model/Settings.java - added method isHighlightMsgEnabled()