Interactions between ContextMediaApp and
CPostStorage/CCMNetwork

both should be created at startup,
CCMNetwork will periodically fetch new posts

When seeing an previously unknown visualcode,
call
	CPostStorage::AddPlaceHolder(visualcode)
and	CCMNetwork::FetchThread(visualcode, 0)

CCMNetwork automatically fetches media files
for new posts, but when selecting a thread or
post the UI should call
	CCMNetwork::FetchMedia
for all interesting posts
so that the currently showing media can be fetched first

CCMNetwork automatically creates icons for new
posts, but again the UI should call 
	CCMNetwork::MakeIcon
to prioritize the creation

All notifications of new posts, media and icons
will be through the MPostNotify interfaces registered
via CPostStorate. 