Injector API restructuring

Injector API:
- Removed socket connection
- Added dynamic API for injections (injection is allowed in all time
after Injector was injected)
- Debugger protocol is extensible now!

Added v8-debug dependence
(Small binary API what allow to extend debugger protocol)
Typo? `_appPausedBuInjector -> _appPausedByInjector`.

Before you go and fix it, why it was not caught by unit-tests? Is the `close` function on covered?