Introduce independent functions, replacing the info struct. Remove hooks support for now; it could be added by reusing hooks.c:check_hook_cmd().
* subversion/include/svn_repos.h (svn_repos_capabilities): Point to this function from the "if you add a new capability" comment. (svn_repos_info_format): New function. (svn_repos_info, svn_repos_info_t, svn_repos_info_dup): Delete declarations (which have never been implemented)..
* subversion/tests/libsvn_repos/repos-test.c (svn_hash.h, svn_version.h): Include. (test_repos_info): New function. (test_funcs): Run it.
* subversion/libsvn_repos/repos.h (SVN_REPOS__FORMAT_NUMBER, SVN_REPOS__FORMAT_NUMBER_1_4): Juggle macros a little to ensure that svn_repos_info_format() would trip if we increment the format number without changing the "format number to version number" logic therein.