The functionality will be added (that is, if I don't get bored) one thing at a time with the spec.
If you want to test, point the libv8 gem (in Gemfile) to its trunk branch & my changes at stormbreakerbg/libv8 @ trunk.
What works currently is getting V8 to initialize, say its version and create a new Isolate.
This fixes segmentation fault in the tests as extending the examples in a before block with override of `#instance_eval` seems to not work.
Also, the context wrap is now opt-in with a helper method, instead of opt-out and relying on `#described_class` (which has slightly different behavior in RSpec 3).
Tested on Ruby 2.1.5 and RSpec 2.99.2.
