Working on isue #4326 (update javahl with new 1.8 APIs).
Add wrapper for svn_repos_freeze.

[in subversion/bindings/javahl/src/org/apache/subversion/javahl]
* ISVNRepos.java: (ISVNRepos.freeze): New abstract method.
  (ISVNRepos.recover): Fix docstring.
* SVNRepos.java (SVNRepos.freeze): Declare native method.
* callback/ReposFreezeAction.java (ReposFreezeAction): New; callback used
   by ISVNRepos.freeze.

[in subversion/bindings/javahl/native]
* ReposFreezeAction.h, ReposFreezeAction.cpp: (ReposFreezeAction):
   C++ implementaiton of the ReposFreezeAction callback.
* SVNRepos.h, SVNRepos.cpp (SVNRepos::freeze):
   Implementation of native method SVNRepos.freeze.
* org_apache_subversion_javahl_SVNRepos.cpp
  (Java_org_apache_subversion_javahl_SVNRepos_freeze): New JNI wrapper.

[in subversion/bindings/javahl/tests/org/apache/subversion/javahl]
* SVNReposTests.java: Update docstrings.
  (FreezeAction, testFreeze): New test case for ISVNRepos.freeze.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1456375 13f79535-47bb-0310-9956-ffa450edef68