Node 12 support

[bdistin]

zlib-sync will not build when using node v12.x.

\node_modules\zlib-sync\src\zlib_sync.cc(72): error C2661: 'v8::Value::BooleanValue': no overloaded function takes 0 arguments [\node_modules\zlib-sync\build\zlib_sync.vcxproj]
\node_modules\zlib-sync\src\zlib_sync.cc(76): error C2660: 'v8::Value::Int32Value': function does not take 0 arguments [\node_modules\zlib-sync\build\zlib_sync.vcxproj]
  \.node-gyp\12.7.0\include\node\v8.h(2576): note: see declaration of 'v8::Value::Int32Value' (compiling source file ..\src\zlib_sync.cc)
\node_modules\zlib-sync\src\zlib_sync.cc(165): error C2660: 'v8::Value::Int32Value': function does not take 0 arguments [\node_modules\zlib-sync\build\zlib_sync.vcxproj]
  \.node-gyp\12.7.0\include\node\v8.h(2576): note: see declaration of 'v8::Value::Int32Value' (compiling source file ..\src\zlib_sync.cc)
\node_modules\zlib-sync\src\zlib_sync.cc(170): error C2661: 'v8::Value::ToString': no overloaded function takes 0 arguments [\node_modules\zlib-sync\build\zlib_sync.vcxproj]
\node_modules\zlib-sync\src\zlib_sync.cc(170): error C2512: 'v8::String::Utf8Value': no appropriate default constructor available [\node_modules\zlib-sync\build\zlib_sync.vcxproj]
  \node_modules\zlib-sync\src\zlib_sync.cc(170): note: No constructor could take the source type, or constructor overload resolution was ambiguous
\node_modules\zlib-sync\src\zlib_sync.cc(178): error C2660: 'v8::Value::Int32Value': function does not take 0 arguments [\node_modules\zlib-sync\build\zlib_sync.vcxproj]
  \.node-gyp\12.7.0\include\node\v8.h(2576): note: see declaration of 'v8::Value::Int32Value' (compiling source file ..\src\zlib_sync.cc)
\node_modules\zlib-sync\src\zlib_sync.cc(204): error C2660: 'v8::FunctionTemplate::GetFunction': function does not take 0 arguments [\node_modules\zlib-sync\build\zlib_sync.vcxproj]
  \.node-gyp\12.7.0\include\node\v8.h(5955): note: see declaration of 'v8::FunctionTemplate::GetFunction' (compiling source file ..\src\zlib_sync.cc)
\node_modules\zlib-sync\src\zlib_sync.cc(204): error C2661: 'v8::Object::Set': no overloaded function takes 1 arguments [\node_modules\zlib-sync\build\zlib_sync.vcxproj]

Would be great to have a version that works for node 12!

[abalabahaha]

#3