Revise JavaHL's ISVNRepos.hotcopy API.

[in subversion/bindings/javahl]
* src/org/apache/subversion/javahl/ISVNRepos.java,
  src/org/apache/subversion/javahl/SVNRepos.java
  (ISVNRepos.hotcopy): Add an overload that adds a notification
   callback to match svn_repos_hotcopy3.

* src/org/apache/subversion/javahl/ReposNotifyInformation.java
  (ReposNotifyInformation.Action): Add new enum constants for 1.9.


* native/SVNRepos.h, native/SVNRepos.cpp
  (SVNRepos::hotcopy): Update.
* native/org_apache_subversion_javahl_SVNRepos.cpp
  (Java_org_apache_subversion_javahl_SVNRepos_hotcopy): Update JNI wrapper.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1618894 13f79535-47bb-0310-9956-ffa450edef68