Avoid a 64-to-32-bit conversion warning in JavaHL.

[in subversion/bindings/javahl]
* native/SVNClient.h, native/SVNClient.cpp (SVNClient::logMessages):
   Change the type of the 'limit' parameter from long to int,
   to match the prototype of svn_client_log5.
* native/org_apache_subversion_javahl_SVNClient.cpp
  (Java_org_apache_subversion_javahl_SVNClient_logMesages):
   Verify that the jlimit argument is within the range of the C int
   type, and cast it accordingly in the call to SVNClient::logMessages.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1603363 13f79535-47bb-0310-9956-ffa450edef68