Added support for profiles' hook_install_tasks_alter implementations.

 	modified:   ProfileInstaller.php
 	modified:   examples/standard2/standard2.install
Minor updates.

 	modified:   profile_installer.inc
Added support for profiles' hook_form_install_configure_form_alter implementations.

	modified:   ProfileInstaller.php
	modified:   examples/standard2/standard2.profile
Added handling for multiple profiles.

 Prevent infinite loop from install_task_alters:
	modified:   ProfileInstaller.php

 Example:
	new file:   examples/standard3/standard3.info
	new file:   examples/standard3/standard3.install
	new file:   examples/standard3/standard3.profile
	new file:   examples/standard3/translations/README.txt
Changed variable/function names: invocation -> implementation.

 	modified:   ProfileInstaller.php
Fixed PHP error.

 	modified:   ProfileInstaller.php
Fixed ProfileInstaller alter handling.

  Now form alters for install_configure_form don't break, and there's some
  groundwork for something more extensible.