BARF's REIL use case: find an execution path to a function

[schomatis]

The translation for the Hexagon architecture is being developed in the reil branch in order to use BARF's REIL analysis tools. As first example of this use, the factorial_example.elf binary of this repository is being analyzed, in order to find all possible execution paths to a chosen function (e.g., malloc) with a particular execution environment (e.g., a specific value as its argument).

This example has as a final application the check of the reachability of CVE-2016-5080 in modem binaries, but it is also useful as a test case to add Hexagon architecture support dynamically to BARF.

Modifications to the BARF source code are being done in a forked repository, and will later be merged to the original project.