Merge pull request #1263 from lakkatv/xmb

(XMB) Display appropriate content icons
Add content_is_init - set to true if content file has been loaded
into memory, set to false when it has failed in doing so
Add check for g_extern.system.no_content as well
init_content_file - set content_is_init to false at start of
function
Don't create empty history file if it does not exist yet - TODO/FIXME -
verify on consoles/mobiles
(XMB) Use MENU_FILE_CONTENTLIST_ENTRY
(XMB) Start displaying a list of action for each content in content lists
(XMB) Revert cd3e0b02f5a5dde6e5dccbf4aa5338ccf6a4764f, let's find a better way to do this