Add missing slotStackLimit checks in DummyContainer
when checking if we can route to X, actually check that we can route to X
don't get yourself over and over.
you only need to convertFromMeta once.
don't get every exit, and use a cache.

cache used because this is only used for texture updates, and testing
for locked non-routing exits.
placing a block to change either of those conditions cause a cache
refresh in the same or next tick.
an an inventory is indexed in a forest and no one is watching ...
be threaded by default.
thread the HUD (updates only)

send 90 slots/tick updates, everything that needs updating in
round-robbin. whole pipes are sent, so something updating 1000 slots
will be the only thing sent that tick, rather than causing a lag-spike.

the manualResetEvent is from
http://stackoverflow.com/questions/1064596/what-is-javas-equivalent-of-manualresetevent
.
multiple releases will simply set the event to open. multiple threads
can wait at a closed lock, and all will be released when it is set.
Merge remote-tracking branch 'lp-dev/Dev' into dev
actually use the fancy new thread ...
Merge remote-tracking branch 'lp-dev/Dev' into dev
check the router for null, if it disapeard between requests.
Merge remote-tracking branch 'lp-dev/Dev' into dev
Merge pull request #537 from AartBluestoke/dev

various cpu efficency improvements