Revert r7770 ("Speed up the regression tests") because, to quote Branko,

Revert r7770 ("Speed up the regression tests") because, to quote Branko,

  The repository loader only depends on the dumpfile parser (which is pretty
  simple and stable) and libsvn_fs, which has its own exhaustive tests. "svn
  import", on the other hand, depends on all the libraries. Therefore, using
  "svnadmin load" to prepare the initial tree give us much better confidence
  that the tests start in a consistent state than using "svn import".

* subversion/tests/clients/cmdline/svntest/actions.py
  (guarantee_greek_repository): Dump and load the greek tree instead of
    importing it.

* subversion/tests/clients/cmdline/svntest/main.py
  (pristine_dir): Restored.

git-svn-id: http://svn.apache.org/repos/asf/subversion/trunk/subversion/tests/clients/cmdline@847855 13f79535-47bb-0310-9956-ffa450edef68