Revision 225226

Working on: MNG-607

o Added '-f' CLI option, to allow use of non-standard pom files, or spawning of a build from outside of the project dir.
o Added preferential processing of release-pom.xml over pom.xml if it exists (assumes that the current checkout is a release of the software)
o Moved all file discovery from MavenCli to DefaultMaven, to allow embedders to have access to this logic.
o Modified MavenExecutionRequest to add a flag for reactor-activation and the name of a non-standard pom to use, if appropriate.
o Removed getFiles() and getProjectFiles() from MavenExecutionRequest, since file discovery is now done in the DefaultMaven.
o Added integration tests to check preference of release-pom.xml in standalone and '-r' mode
o Added integration tests to check usage of '-f' option within and outside of the project directory
o Added processing for cli-options.txt to maven-core-it-verifier (Verifier.java) to allow specification of '-f' and '-r' in tests


NOTE: the release plugin still doesn't correctly remove the release-pom.xml from HEAD/trunk, since I don't have access to the SCM remove command from maven-scm. I'm waiting for Emmanuel to finish some API changes before moving to the new maven-scm version, and implementing this final step.