Add in a new spooky.exec(code) method for evaluating code within a CasperJS context.
Add in options argument to the exec method.
Add in the ability to specify a file to execute as part of the options to Spooky.
Change the option formatting for 'exec' and add in a test to verify that it works as expected.
Merge branch 'exec' of https://github.com/jeresig/SpookyJS into jeresig-exec

Conflicts:
	lib/bootstrap/stdio-server.js