deps: v8 - cosmetic build adjustments

this is in order to give a better development experience in MSVS
eventually should land in v8 trunk
tools: build adjustments for v8 3.29

- Getting it to compile and be sane
- Removed references to v8::Debug*
build: added `verbose` argument to build tools
build: fix or suppress warnings

- activated "treat warnings as errors"
src: re-implement debug-agent

- based on discarded v8 code
tools: benchmark + testing fix + cpplint.py

- Improve benchmark suite (can run all test)
- Improve test suite
- Update `cpplint.py` but exclude all new warnings
  - allows for c++11 as per https://groups.google.com/d/msg/v8-users/o1wffwdnUdU/EKzlsTDd-KgJ
crypto: remove duplicate declaration

Caused crashes in `Debug`
test: fixture certificate expired
test: tweaking test code

test-child-process-fork-net2.js - time limit too strict
test-cluster-worker-init.js - time limit too strict
test-force-repl.js - time limit too strict
test-fs-empty-readStream.js - time limit too strict
test-fs-realpath.js - Windows case normalization
test-fs-realpath.js - Windows case normalization
src: protect in case there is no toString()

triggered by test-regress-GH-4015.js with Debug build