The Perl process was exiting directly when called but that interfered with proper locking for the forked async process. Now Perl returns results to the C process which handles all errors, including signals.
Now only two types of locks can be taken: archive and backup. Most commands use one or the other but the stanza-* commands acquire both locks. This provides better protection than the old command-based locking scheme.
Move command begin to C except when it must be called after another command in Perl (e.g. expire after backup). Command begin logs correctly for complex data types like hash and list. Specify which commands will log to file immediately and set the default log level for log messages that are common to all commands. File logging is initiated from C.
* Remove --reset tags from v1 options.
* Use constants for repo prefix.
* Specify CFGDEF_INDEX_PG in option structure rather than adding in code.
* Fix error message references to "backup host".
Contributed by Cynthia Shang.
