Add 'pause' action plugin and support plugins skipping the host loop.

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<tbielawa>@(griddle)[~/Projects/ansible] 1:13:47  (runner_pause)
$ git log -1
commit 58a4d2f7b4551b6222f9def382cac87970fc3aea
Author: Tim Bielawa <tbielawa@redhat.com>
Date:   Sat Sep 22 02:07:49 2012 -0400

    Add 'pause' action plugin and support plugins skipping the host loop.

<tbielawa>@(griddle)[~/Projects/ansible] 1:13:51  (runner_pause)
$ make tests
PYTHONPATH=./lib nosetests -v
test_complex_enumeration (TestInventory.TestInventory) ... ok
test_complex_exclude (TestInventory.TestInventory) ... ok
test_complex_vars (TestInventory.TestInventory) ... ok
Test the case when playbook 'hosts' var is a list. ... ok
test_script (TestInventory.TestInventory) ... ok
test_script_all (TestInventory.TestInventory) ... ok
test_script_combined (TestInventory.TestInventory) ... ok
test_script_norse (TestInventory.TestInventory) ... ok
test_script_restrict (TestInventory.TestInventory) ... ok
test_script_vars (TestInventory.TestInventory) ... ok
test_simple (TestInventory.TestInventory) ... ok
test_simple_all (TestInventory.TestInventory) ... ok
test_simple_combined (TestInventory.TestInventory) ... ok
test_simple_norse (TestInventory.TestInventory) ... ok
test_simple_port (TestInventory.TestInventory) ... ok
test_simple_restrict (TestInventory.TestInventory) ... ok
test_simple_ungrouped (TestInventory.TestInventory) ... ok
test_simple_vars (TestInventory.TestInventory) ... ok
test_one (TestPlayBook.TestPlaybook) ... ok
test_playbook_vars (TestPlayBook.TestPlaybook) ... ok
test_yaml_hosts_list (TestPlayBook.TestPlaybook) ... ok
test_assemble (TestRunner.TestRunner) ... ok
test_async (TestRunner.TestRunner) ... ok
test_command (TestRunner.TestRunner) ... ok
test_copy (TestRunner.TestRunner) ... ok
test_facter (TestRunner.TestRunner) ... ok
test_fetch (TestRunner.TestRunner) ... ok
test_file (TestRunner.TestRunner) ... ok
test_git (TestRunner.TestRunner) ... ok
test_large_output (TestRunner.TestRunner) ... ok
test_ping (TestRunner.TestRunner) ... ok
test_parse_kv_basic (TestUtils.TestUtils) ... ok
test_template_basic (TestUtils.TestUtils) ... ok
test_template_unicode (TestUtils.TestUtils) ... ok
test_template_varReplace_iterated (TestUtils.TestUtils) ... ok
test_template_whitespace (TestUtils.TestUtils) ... ok
test_varLookup_list (TestUtils.TestUtils) ... ok
test_varReplace_almost_alternative (TestUtils.TestUtils) ... ok
test_varReplace_almost_alternative2 (TestUtils.TestUtils) ... ok
test_varReplace_alternative (TestUtils.TestUtils) ... ok
test_varReplace_alternative_greed (TestUtils.TestUtils) ... ok
test_varReplace_caps (TestUtils.TestUtils) ... ok
test_varReplace_include (TestUtils.TestUtils) ... ok
test_varReplace_include_script (TestUtils.TestUtils) ... ok
test_varReplace_invalid_list (TestUtils.TestUtils) ... ok
test_varReplace_list (TestUtils.TestUtils) ... ok
test_varReplace_list_nolist (TestUtils.TestUtils) ... ok
test_varReplace_list_oob (TestUtils.TestUtils) ... ok
test_varReplace_middle (TestUtils.TestUtils) ... ok
test_varReplace_multiple (TestUtils.TestUtils) ... ok
test_varReplace_nested (TestUtils.TestUtils) ... ok
test_varReplace_nested_int (TestUtils.TestUtils) ... ok
test_varReplace_nested_list (TestUtils.TestUtils) ... ok
test_varReplace_notcomplex (TestUtils.TestUtils) ... ok
test_varReplace_simple (TestUtils.TestUtils) ... ok
test_varReplace_unicode (TestUtils.TestUtils) ... ok

----------------------------------------------------------------------
Ran 56 tests in 42.295s
````