Feature changes to support concrete execution. (#337)
Feature changes to support concrete execution. (#337)

* Feature changes to support concrete execution.

- Add ctypes to lseek for signed seeks. Pass whence to seek.
- Move mmap and related functions from SLinux to Linux.
- Introduce function _sys_open_get_file to isolate symbolic code in sys_open to SLinux.

* Remove white space, use super(...)._sys_open_get_file, self.current.address_bit_size.

trailofbits/manticore,trailofbits/manticore,montyly/manticore,montyly/manticore,trailofbits/manticore