Update SIMPLEXpress to use IOChannel

Summary:
Remove unneeded includes and using statements

Change std::cout to channel (IOSqueak)

Test Plan: Verify with included Goldilocks tests

Reviewers: jcmcdonald, memateo, wdede, mahussain

Reviewed By: jcmcdonald

Subscribers: ardunster

Tags: Programming [Dept], SIMPLEXpress [Project]

Maniphest Tasks: T1461

Differential Revision: https://phabricator.mousepawmedia.net/D400