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)
It's a true change. I don't need to test ```pausing``` API here. I only need to setup application in debug-brk mode and connect.
Good point is, that I need to pass all this ```describe``` block to the end of test file (after ```describe('with inject=true and debug-brk flag', function() {```)