0.1.2

Makefile loading no longer starts a build automatically.
Added explicit make form: (make), (make target), and (make target ...).
Command-line use is now: racket -t Makefile.rkt -e "(make target)".
DrRacket can load the makefile with Run and execute make forms interactively.
Bare identifiers in make are always interpreted as literal target names.
Expanded documentation and examples for command-line and DrRacket use.

0.1.1

Initial racket-makefile language implementation.

Targets and dependencies with timestamp based rebuilding.
Phony and default targets.
Direct external command execution with run.
Recipe values $target, $deps and $<.
Cleanup helpers rm-f, rm-rf and cleanup.
Scribble documentation and example Makefile.
