Add memory usage profiling feature

Add memory usage profiling feature

This patch adds memory usage profiling feature while in runtime.

Basially, there are some procfs to collect memory usage consumed
by current process, and we use /proc/self/stat.

These memory usage data are updated by Linux kernel scheduler so
they should be measured before and after current process.

As for this, this patch adds a new script file, start_profiler.sh.
SO if you want to profile exact memory usage in runtime then
run ./start_profiler.sh on Target.

Ps. the memory usage data can be measred by inference_engine_test app
but the data wouldn't be exact.

Change-Id: I5416587d4847c65538768b15f69f1e23862e2837
Signed-off-by: Inki Dae <inki.dae@samsung.com>