Initial commit for ktap

ktap is a new dynamic tracing tool for Linux, it is a script environment
running in Linux kernel(similar with systemtap and Dtrace).

ktap is GPL licensed, the compiler and virtual machine is borrowed
from lua language as initial implementation.

compiler and loader is included in userspace tool ktap

compiling:
    make ktap    --- generate userspace ktap tool
    make         --- generate ktapvm kernel module

try to running ktap:
    ./ktap scripts/tracepoint.ktap

This commit is just a initial pulbic code release, it have basic
tracepoint and syscall support, please waiting ktap release 1.0. :)

I suggest you put this ktap directory into linux/kernel/trace/.

(this initial code have one issue: it need to patch ftrace code in Linux kernel,
 see ftrace.patch, I will try to get rid it sooner.)

For any question, please contact the anthor, Jovi Zhang.

ktap is a open source project, welcome hacking and contributing.

Signed-off-by: Jovi Zhang <bookjovi@gmail.com>