More helpful example in Test.hs

Before:
    + ./dist/build/shake-test/shake-test --help
    Welcome to the Shake demo

    Modes: clean test make
    Demos: tar self c basic cache command directory docs errors filepath filepattern files journal lint makefile pool random resources assume benchmark oracle progress

    As an example, try:

      main self --threads2 --loud

    Which will build Shake, using Shake, on 2 threads.





After (GHC 7.4.2):
    + ghc --version
    The Glorious Glasgow Haskell Compilation System, version 7.4.2
    + ./dist_74/build/shake-test/shake-test --help
    Welcome to the Shake demo

    Modes: clean test make
    Demos: tar self c basic cache command directory docs errors filepath filepattern files journal lint makefile pool random resources assume benchmark oracle progress

    As an example, try:

      shake-test self --jobs=2 --trace

    Which will build Shake, using Shake, on 2 threads.





After (GHC 7.6.2):
    + ghc --version
    The Glorious Glasgow Haskell Compilation System, version 7.6.2
    + ./dist_76/build/shake-test/shake-test --help
    Welcome to the Shake demo

    Modes: clean test make
    Demos: tar self c basic cache command directory docs errors filepath filepattern files journal lint makefile pool random resources assume benchmark oracle progress

    As an example, try:

      /home/jchee/packages/shake/dist_76/build/shake-test/shake-test self --jobs=2 --trace

    Which will build Shake, using Shake, on 2 threads.