fix TLS crash by removing obsolete twitter-stream patch

earthquake is working around an issue in old releases of
twitter-stream where reconnections were not honouring
@options[:ssl].

This issue was fixed in twitter-stream-0.1.15, and the now
unnecessary monkey-patch crashes the program upon reconnect.

Require twitter-stream ~> 0.1.15 and remove the monkey-patch
to make the crashes go away.
use twitter-stream's reconnect-on-timeout behaviour

twitter-stream ~> 0.1.16 takes care of reconnecting when no data has
been received for a while.  With earthquake also doing this, strange
behaviour occurs when twitter-stream 0.1.16 is used.

Update the dependency to twitter-stream ~> 0.1.16 and remove the
reconnect-on-timeout code from Earthquake::Core to restore normal
behaviour.