Logmaker/FunctionTracer: add the initial version of FunctionTracer

[Freakston]

Logmaker/FunctionTracer: add the initial version of FunctionTracer

In this I've added the initial version of FunctionTracer. The Current version checks out the following features from issue #9.

• [X] Iterate through the entire program and get details on all the function calls

• [X] Sort whether each call is a library call or a user defined call

• As of now it only prints out a few functions that I've hand picked

• [X] Store statistics of each function call (ie how many times is it called)

• There is a small issue with the numbering. I'm currently looking into why it's wrong in a few cases For ex: Ptrace

• [X] Sort function calls - by callee functions

• The functions are printed in the same order as they are called.

A gist containing the output of Pintool is as follows - Link

[R3x]

I am merging this. At a glance everything looked good.