Version Control With Subversion Source

usage does not work properly, and specify the default revision range because
it differs between URL and local usage and has confused people.

* doc/book/book/ch08.xml
* subversion/clients/cmdline/main.c
* subversion/tests/clients/cmdline/getopt_tests_data/svn_help_log_switch_stdout
In the help for "svn log", do not allow multiple local paths, and specify
the default revision range.