ftracetest: Initial commit for ftracetest

ftracetest is a collection of testcase shell-scripts for ftrace.
To avoid regressions of ftrace, these testcases check correct
ftrace behaviors. If someone would like to add any features on
ftrace, the patch series should have at least one testcase for
checking the new behavior.

Link: http://lkml.kernel.org/p/20140922234250.23415.68758.stgit@kbuild-f20.novalocal
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>