Allow Release builds with the build command.
- build.proj sets the current working dir to build/$(Config)
- storytest.config.xml paths rebased per the above
- All affected test pages rebased per the above
- Net result: uglier test pages, but you can do:
  $ build "/p:Config=Release"
  and have build, unittest and storytest happen
  on the built release binaries.
Revert "Allow Release builds with the build command."

This reverts commit 61bb56ec2339ff5e6ae9e9a4ba41a896a1f31d0c.
Allow Release builds with the build command.

* build.cmd copies all artifacts to configuration-independent build/sandbox
* Unit tests and story tests now refer to build/sandbox instead of build/debug
* Test pages refer to build/sandbox instead of build/debug
* Storytest configuration files refer to build/sandbox instead of build/debug
* Fitnesse metadata refer to build/sandbox instead of build/debug

This allows us to pass a configuration value to build.cmd using:

  build.cmd "/p:Config=Release"

and have the entire build pipeline work on Release binaries.

However, it also means we can't debug test pages from Visual Studio
without first building from command-line, because the sandbox will not
be set up.
Merge remote-tracking branch 'upstream/master' into undebug
Merge branch 'dev-undebug' into undebug
Merge pull request #112 from kimgr/undebug

Allow Release builds with the build command.