Context-aware initialization allows to instantiate add-ons multiple
times, most importantly in multiple Workers' contexts. Workers made
first appearance in v10.5. Context-aware initialization was option
earlier than that, even before supported minimum v6.x, yet condition
is chosen more conservatively as NODE_MODULE_VERSION >= 64, a.k.a.
v10.0.
* js-v8-52-tests:
fixed nvm
node tests: use provided version if present
travis tests for different node versions
fix travis tests
Test NodeJS 4, 6, 8, and 10
Remove warnings on Node 6.x aka V8 5.0 and 5.1
Add Node 7.x aka V8 5.2+ support
The proposed changes targetted at 5.2 (or 5.4 to be more precise, since there is no Node release with V8 5.2 or 5.3) work for lower versions as well and bust the deprecation warnings there.
* Use WeakCallbackInfo instead of WeakCallbackData
* Use GetPrivate instead of GetHiddenValue
* Adopted new signature for SetWeak to support destructor calling
* SetAccessor deprecation fixed
* Proper version checks where applicable
