Require the sqlite3 module for running the python testsuite.

Require the sqlite3 module for running the python testsuite.

This most likely breaks the windows buildbot, as it does not currently have
the python sqlite3 module installed.

The discussion is here: http://svn.haxx.se/dev/archive-2009-09/0557.shtml

* subversion/tests/cmdline/upgrade_tests.py
  Import sqlite3 at the top level.
  (check_formt, check_dav_cache): Don't import sqlite3.
  (has_sqlite): Remove.
  (test_list): Don't make running tests conditional on the existence of the
    sqlite3 module (since we're now guaranteed to have it).

* subversion/tests/cmdline/svntest/__init__.py:
  Attempt to import sqlite3, and if we can't, die a horrible death.
  (With a friendly error message, of course.)

git-svn-id: http://svn.apache.org/repos/asf/subversion/trunk/subversion/tests/cmdline@879785 13f79535-47bb-0310-9956-ffa450edef68