Adds `load_package_tests` function to test.support, uses it in test_asyncio,
test_email, test_json, test_tools, test_importlib and all test_importlib
sub-packages to implement test discovery.

#18273: move the tests in Lib/test/json_tests to Lib/test/test_json and make them discoverable by unittest.  Patch by Zachary Ware.

Approved by Raymond Hettinger.

svn+ssh://pythondev@svn.python.org/python/trunk

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  r62734 | brett.cannon | 2008-05-05 22:21:38 +0200 (Mon, 05 May 2008) | 5 lines

  Add the 'json' package. Code taken from simplejson 1.9 and contributed by Bob
  Ippolito.

  Closes issue #2750.
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  r62736 | georg.brandl | 2008-05-05 22:53:39 +0200 (Mon, 05 May 2008) | 2 lines

  Fix JSON module docs.
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  r62748 | benjamin.peterson | 2008-05-06 04:51:10 +0200 (Tue, 06 May 2008) | 2 lines

  PEP 8 nits in json package
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  r62769 | christian.heimes | 2008-05-06 18:18:41 +0200 (Tue, 06 May 2008) | 2 lines

  Intern static string
  Use float constructors instead of magic code for float constants
........

Ippolito.

Closes issue #2750.