Revert "added compiler object and agent object to support the agent abstraction"

This reverts commit 086533c1d86b223bb29064130c2c72167ed10057.
Merge branch 'master' of https://github.com/mikelevins/bard

Conflicts:
	0.4/lisp/src/agent.lisp
	0.4/lisp/src/compiler.lisp
	0.4/lisp/src/globals.lisp