Uses environment variables defined in phpunit.xml in ConfigTest.
Outputs install logs to stdout.

* add --stdout option to InstallCommand.
* use tee command in CommandBuilder when --stdout is given.
Merge pull request #437 from shinnya/feature/stdout

Outputs install logs to stdout.
Make InstallCommandTest faster.
Merge pull request #436 from shinnya/feature/make-tests-faster

Make InstallCommandTest faster.
Replace patches using sed and perl with pure php.

* Define PHPBREW_EXPECTED_PHP_DIR and PHPBREW_FIXTURES_PHP_DIR in
  phpunit.xml.
* Add a common interface of patch utility classes.
* Add a new class RegexpPatch which replaces a content of files using regexp.
* Introduce PatchCollection class and it holds patch definitions now.
* Add tests for Apxs2PatchTask, Patch64BitSupportTask, RegexpPatch,
  PatchCollection, and RegexpPatchRule.
* Add an utility class which provides a way to create temprary files in
  tests.
Merge pull request #435 from shinnya/feature/replace-sed-and-perl

Replace patches using sed and perl with pure php.
Merge pull request #424 from shinnya/fix/use_predefined_environment_variables

Uses predefined environment variables in ConfigTest.
Refactors InstallCommand to use DefaultBuildSettings.