Don't crash on null error

This happens if you try and debug a stuck process using

    gdb> print 'v8::V8::TerminateExecution'(0)

from http://remysharp.com/2013/09/11/how-i-fixed-an-anonymous-infinite-loop-in-jsbin/
Fix Utils.fullPath on Windows

Utils.fullPath was expecting an absolute path to start with the path
separator -- which works great on *nix but fails on Windows. Luckily,
replacing the logic with path.resolve provides equivalent functionality
that works across all platforms.
Fix test on Windows

Fix a hardcoded *nix style path separator in the test to use the os
specific version from path.sep.
Make "spec" reporter the default for mocha

It was in the Gruntfile this way, just in the wrong section -- I'm just
putting it where it belongs (Per Simon M).
Add travis
Remove 0.8
Add hipchat
Merge pull request #27 from dpolivy/windows-fixes

Fix the notifier to work better on Windows
Merge pull request #24 from bugsnag/null-error

Don't crash on null error