Error compiling when using v8 3.29

[waTeim]

Hi all, I'm working on combining atom-shell, Julia, and d3 to be used as a data visualizer. D3 needs contextify, but the problem is that the released versions of node use a earlier version of v8.

node 0.10.35:    3.14.5.9
node 0.11.13:    3.25.30
node 0.11.14:    3.26.33
atom-shell:      3.29.88.17

In v8 3.29, the function ContextDisposedNotification is no longer a static member function of the class V8, but rather a member function of v8::Isolate, and so contextify.cc will not compile

 CXX(target) Release/obj.target/contextify/src/contextify.o
../src/contextify.cc:31:13: error: no member named 'ContextDisposedNotification' in namespace 'v8'

Luckily atom-shell provides sufficient defines to conditionally compile

[valer-cara]

Deprecation here: v8/v8@a56c917#diff-3dd7a0f46b1e5c1cc67921449e7180acL5026

[domenic]

Consolidating into #149.