Latest runtime changes

[Martin Hunt]

Anyone using the runtime will need some changes to work with the latest
version.  Examples and documentation is up-to-date in CVS.

What needs changed:

1. I moved init_module into runtime.h.  It initializes the transport
code and calls probe_start(). So you need to rename init_module() in
your modules to probe_start() and remove the transport code from that.
See any example probe in CVS for an example.

2. Remove cleanup_module() and MODULE_LICENSE from your probes.  Those
are now in runtime.h.

New Stuff:

Earlier this week I checked in new functions to handle warnings, errors,
and dbug statements.  Also there is a new function _stp_exit() that
causes a probe to exit ASAP.

See 
http://sources.redhat.com/systemtap/runtime/group__io.html

You can build probes with debugging enabled like this:

> ./build debug
Building test4
Done
> ./stp test4.ko
_stp_register_jprobes:46: inserting jprobe at sys_open (ffffffff8017442b)
_stp_register_jprobes:46: inserting jprobe at sys_read (ffffffff80174de1)
_stp_register_jprobes:46: inserting jprobe at sys_write (ffffffff80174e4f)
Press Control-C to stop.
_stp_unregister_jprobes:25: All jprobes removed