Merge branch 'devel' of github.com:oliver----/swig-v8 into devel
Add pre-processor defines to detect the javascript engine.
Add more ignores.
Fix v8 string conversion in case of null arguments.
Add preprocessor define for building node.js extensions.
Add missing return statement in v8 code template.
Add an ifndef-guard to resolve a warning when building nodejs extension.
Bugfix: treat persistent V8 references correctly.

V8 is somewhat inconvenient regarding invoke of destructors for C++ proxies.
Remove std::iostream relicts from generated v8 wrapper code.
added missing javascript/v8 dir
generate v8-3.19.x compatible code
replaced GetInternalField with GetAlignedPointer (it does not work with SetAlignedPointer, btw)
added missing scope.Close()
converted function templates to the persistent ones (fixed crash on large wrappers)
fixed overloaded functions multiplication
Merge replayed as done by c778d16abed35829b103d607a53c8f88e3b2d595
added virtual dtor to V8ErrorHandler
fixed crash while instantiating generic-wrapped objects from external code, please review
Get memory updates working with Node.js again.
Added #if defined guard for V8_3_14 to allow users from the original SWIG v8 implementation to continue using the new changes. It works similarly to the BUILDING_NODE_EXTENSION in all but two places. This define must be explicitly set by users  because there is no way to auto detect. (Perhaps a command line switch can be added to generate this on request?)