npm install fails

[atvanguard]

In file included from ../../nan/nan.h:192:
../../nan/nan_maybe_43_inl.h:112:15: error: no member named 'ForceSet' in 'v8::Object'
  return obj->ForceSet(isolate->GetCurrentContext(), key, value, attribs);

This is a known issue with older version of nan package (<= 2.7) with newer versions of node (>= 10).

[0xAshish]

@atvanguard please try it with node@8.11.3. some crypto packages are on node8.

[atvanguard]

Fix is trivial. do you think regenerating package-lock could have side-effects?

[0xAshish]

will see if anything fails in CI(should work fine), thanks for PR 👍.