Non-blocking TCP connect; some edits for Arduino 1.5; a fix for duplicate packet spam

Added non-blocking TCP connect, with example code
Some edits for Arduino IDE 1.5

A fix for duplicate packet spam (needs a better fix, setting the timer
thing too low brings back the spam):
Changed uip_timer_reset() to uip_timer_restart(). When using uip_timer_reset() and if its been a while (say, 5 seconds) since the last call to UIPEthernet::tick() then uip_timer_expired() will return true for its next 20 calls since uip_timer_reset() only adds to the timer whatever the timer interval is set to. Setting the interval to 250 also seems a bit high, the minimum latency achievable with that setting is ~500ms. Ultimately we need to figure out why it's sending the same packet multiple times and fix that.