fix(timer): fix #437, #744, fix nativescript timer and nodejs 0.10.x timer issue

[JiaLiPassion]

1. fix zone.js issue with NativeScript #437, native script load timer module failed issue, if failed to load timer, just patch global.setTimeout
2. fix fix double patched timers in older node versions #744, in nodejs 0.10.x, global.setTimeout use timers.setTimeout but not equal, we should avoid to double patch the timer. We should check if global.setTimeout use timers.setTimeout but not equal, we only set zone_symbol for consistency and then don't patch it at all in nodejs 0.10.x or other similar situation.